No change in Scope Clause in new United's pilot contract that would have allowed E175-E2 or else. Delta and AA will follow suit shortly:

"United was the first carrier to negotiate a new agreement with pilots. American Airlines also negotiated a new agreement, following UAL. There were no changes to Scope weights, either. UAL’s union, ALPA, only today confirmed no change to its contract. It is now highly unlikely Delta Air Lines or Alaska Airlines, whose pilots are also represented by ALPA, will change."

https://leehamnews.com

So, how will Regional Carriers deal with no new scope clause compliant regional jet to replace E1-175s after the 2027 ?

docmtl

Personally, I think Embrear is positioning the E3 to be the E175 replacement, and I wouldn’t be surprised if we see engine options other than the turboprops (like open rotor)

There is absolutely no reason the majors would conceed to the demands to change scope. This will reduce regional jet flying.

Personally, I am a fan of less than daily P2P service. The airlines setup for that will grab the trunk routes.

A new turboprop will takeover some routes.

However, the reduction in 50 seater service is already severing some cities from the legacy networks. e.g., one relative, lifetime platinum on Northwest and now Delta, lives in a city cutoff now from the Delta network.

We will see many cities only served by one or two of the legacies. I see Breeze, Allegiant, Frontier, and Spirit (no matter who buys them).

Perhaps the legacies will be able to negotiate ground contracts to bring in mainline a few days per week? Hey, isn't Delta's ground non-union?

docmtl wrote:

No change in Scope Clause in new United's pilot contract that would have allowed E175-E2 or else. Delta and AA will follow suit shortly:

"United was the first carrier to negotiate a new agreement with pilots. American Airlines also negotiated a new agreement, following UAL. There were no changes to Scope weights, either. UAL’s union, ALPA, only today confirmed no change to its contract. It is now highly unlikely Delta Air Lines or Alaska Airlines, whose pilots are also represented by ALPA, will change."

https://leehamnews.com

So, how will Regional Carriers deal with no new scope clause compliant regional jet to replace E1-175s after the 2027 ?

docmtl

That's incorrect. In the UAL TA, there is a proposed weight change as the CRJ-550 weight would increase 4,750 pounds. I'm surprised (not to mention, disappointed) that UAL ALPA agreed to such a change give the rare leverage the pilots have right now.

Velocirapture wrote:

docmtl wrote:

No change in Scope Clause in new United's pilot contract that would have allowed E175-E2 or else. Delta and AA will follow suit shortly:

"United was the first carrier to negotiate a new agreement with pilots. American Airlines also negotiated a new agreement, following UAL. There were no changes to Scope weights, either. UAL’s union, ALPA, only today confirmed no change to its contract. It is now highly unlikely Delta Air Lines or Alaska Airlines, whose pilots are also represented by ALPA, will change."

https://leehamnews.com

So, how will Regional Carriers deal with no new scope clause compliant regional jet to replace E1-175s after the 2027 ?

docmtl

That's incorrect. In the UAL TA, there is a proposed weight change as the CRJ-550 weight would increase 4,750 pounds. I'm surprised (not to mention, disappointed) that UAL ALPA agreed to such a change give the rare leverage the pilots have right now.

I mean the 550 is just a paper airplane. What do the pilots have to loose, they are just changing CR7 into CR5

Velocirapture wrote:

That's incorrect. In the UAL TA, there is a proposed weight change as the CRJ-550 weight would increase 4,750 pounds. I'm surprised (not to mention, disappointed) that UAL ALPA agreed to such a change give the rare leverage the pilots have right now.

Yes, there is a weight increase along with a new hard flight distance cap of 900 miles to prevent the allowed increased weight from being used to fly longer routes. Passenger weights went up resulting in weight restrictions on these aircraft. In theory that’s a good thing, but the company is not going to stop flying these planes for now. The increased passenger weights and weight restrictions have resulted in numerous UAL pilots being denied the jumpseat when these aircraft are put on a route. The TA language weight increase will allow for 50 passengers as intended plus a jumpseat rider without an increase in flight length.

WayexTDI wrote:

flyinggoat wrote:

Personally, I think Embrear is positioning the E3 to be the E175 replacement, and I wouldn’t be surprised if we see engine options other than the turboprops (like open rotor)

But what's really the difference between a turbo-prop and an open rotor? Number and shapes of the blades, but the principal is the same.
I'd say a turbo-prop and an open rotor are as similar as a regular turbofan and a geared turbofan.

If the public is scared of turbo-props, they'll be scared of open rotors.

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency.

The rotor technology is more similar to a turbofan, than a turboprop. So it represents an intermediate technology.

The latest GE turbofans are optimized for thermal efficiency, while the P&W geared turbofans are optimized for propulsive efficiency. The overall engine efficiency is the product of the two. The open rotor is a compromise solution that attempts to optimize both at the same time, but for a lower cruise speed range, that is still well above that of a turboprop.

Avatar2go wrote:

WayexTDI wrote:

flyinggoat wrote:

Personally, I think Embrear is positioning the E3 to be the E175 replacement, and I wouldn’t be surprised if we see engine options other than the turboprops (like open rotor)

But what's really the difference between a turbo-prop and an open rotor? Number and shapes of the blades, but the principal is the same.
I'd say a turbo-prop and an open rotor are as similar as a regular turbofan and a geared turbofan.

If the public is scared of turbo-props, they'll be scared of open rotors.

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency.

The rotor technology is more similar to a turbofan, than a turboprop. So it represents an intermediate technology.

The latest GE turbofans are optimized for thermal efficiency, while the P&W geared turbofans are optimized for propulsive efficiency. The overall engine efficiency is the product of the two. The open rotor is a compromise solution that optimizes both at the same time.

What kind of speed ranges does an open rotor have compared to turboprops? I find the idea of it being implemented on future aircraft interesting and wonder why it hasn't taken off yet ( yeah, pun intended ).

With the way things are going with oil prices and the pilot shortage, it may be a stretch to assume that regional airlines even exist in 2027....

At some point its just going to be cheaper to fly less frequencies with a 319, 737, 190, 220, etc. If a market is too small to be able to support 2x mainline aircraft a day, its probably too small to be worth serving at all.


Could we see them shut down with a small portion of their fleets... say 50-100 planes per major (such as the newest build CRJ-700s or E175s)... being folded into mainline for service to small premium heavy airports that need that type? For example, ASE and HHH.

9252fly wrote:

Avatar2go wrote:

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency.

The rotor technology is more similar to a turbofan, than a turboprop. So it represents an intermediate technology.

The latest GE turbofans are optimized for thermal efficiency, while the P&W geared turbofans are optimized for propulsive efficiency. The overall engine efficiency is the product of the two. The open rotor is a compromise solution that optimizes both at the same time.

What kind of speed ranges does an open rotor have compared to turboprops? I find the idea of it being implemented on future aircraft interesting and wonder why it hasn't taken off yet ( yeah, pun intended ).

The main factor in the fate of open rotor is the need for fuel efficiency. That fell away in the oil boom of the 90's, and turbofans also continued to improve. Now there are not major gains expected from future turbofans, the low hanging fruit having already been picked. And oil prices are rising again.

Here is a plot of efficiency vs Mach number for the various engine types. I should mention that open rotor has a very high bypass ratio, as compared to a turbofan, but at the expense of reduction in cruise speed, without the shrouded enclosure of the tips. Also the turbofan range depicted here is below that of current engines. Today the turbofan would probably cross the open rotor range at Mach 0.9 or above.

mikejepp wrote:

With the way things are going with oil prices and the pilot shortage, it may be a stretch to assume that regional airlines even exist in 2027....

At some point its just going to be cheaper to fly less frequencies with a 319, 737, 190, 220, etc. If a market is too small to be able to support 2x mainline aircraft a day, its probably too small to be worth serving at all.


Could we see them shut down with a small portion of their fleets... say 50-100 planes per major (such as the newest build CRJ-700s or E175s)... being folded into mainline for service to small premium heavy airports that need that type? For example, ASE and HHH.

That’s a pretty dire prediction. At United’s three largest hubs over 50% of the departures were regional in 2019.

viewtopic.php?t=1420611

Why not bring these operations in house? Why do American legacies need a third party company to operate smaller aircraft? Mom-American carriers such as Ethiopian Airlines operate everything from prop jets to 777s.

It would seem that both sides would benefit. The pilots wouldn’t be competing with pilots from other companies. The airlines would have a signal large pool of pilots which could be scheduled more efficiently than several smaller pools of pilots who are walled off from operating flights that have been contracted to different companies. Not to mention, the poor operational reliability of many regional airlines.

Yossarian22 wrote:

Why not bring these operations in house? Why do American legacies need a third party company to operate smaller aircraft? Mom-American carriers such as Ethiopian Airlines operate everything from prop jets to 777s.

It would seem that both sides would benefit. The pilots wouldn’t be competing with pilots from other companies. The airlines would have a signal large pool of pilots which could be scheduled more efficiently than several smaller pools of pilots who are walled off from operating flights that have been contracted to different companies. Not to mention, the poor operational reliability of many regional airlines.

I'm pondering if this might happen in a few years with AA and their wholly owned regionals. Given that the rumor (or announced) info is that they're increasing pilot wages at the wholly owned regionals. I could those merging with AA at some point, but the company would want the ability to outsource some of those planes.

Now the question is, you'll still have "walled off" pilots, since there are type ratings and the like. What I'm curious if there really is enough cost in the wholly owned regionals that would be able to be cut out? There probably is some, but probably not a lot.

EWRflyr wrote:

Velocirapture wrote:

That's incorrect. In the UAL TA, there is a proposed weight change as the CRJ-550 weight would increase 4,750 pounds. I'm surprised (not to mention, disappointed) that UAL ALPA agreed to such a change give the rare leverage the pilots have right now.

Yes, there is a weight increase along with a new hard flight distance cap of 900 miles to prevent the allowed increased weight from being used to fly longer routes. Passenger weights went up resulting in weight restrictions on these aircraft. In theory that’s a good thing, but the company is not going to stop flying these planes for now. The increased passenger weights and weight restrictions have resulted in numerous UAL pilots being denied the jumpseat when these aircraft are put on a route. The TA language weight increase will allow for 50 passengers as intended plus a jumpseat rider without an increase in flight length.

The 65,000 lb CRJ-550 is only capable of 600nm flights. See thread viewtopic.php?f=3&t=1435369

So adding 4750lbs and limiting range to 900 miles is a significant scope relaxation. Among other things in this TA the pilots aren't going to allow that period. UA knows this already. This is just a negotiating ploy - demand more than you are willing to compromise down to.

Avatar2go wrote:

WayexTDI wrote:

flyinggoat wrote:

Personally, I think Embrear is positioning the E3 to be the E175 replacement, and I wouldn’t be surprised if we see engine options other than the turboprops (like open rotor)

But what's really the difference between a turbo-prop and an open rotor? Number and shapes of the blades, but the principal is the same.
I'd say a turbo-prop and an open rotor are as similar as a regular turbofan and a geared turbofan.

If the public is scared of turbo-props, they'll be scared of open rotors.

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency.

The rotor technology is more similar to a turbofan, than a turboprop. So it represents an intermediate technology.

The latest GE turbofans are optimized for thermal efficiency, while the P&W geared turbofans are optimized for propulsive efficiency. The overall engine efficiency is the product of the two. The open rotor is a compromise solution that attempts to optimize both at the same time, but for a lower cruise speed range, that is still well above that of a turboprop.

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency, AND AT THE COST OF HIGHER NOISE LEVELS.

fixed it for you

USAirKid wrote:

Yossarian22 wrote:

Why not bring these operations in house? Why do American legacies need a third party company to operate smaller aircraft? Mom-American carriers such as Ethiopian Airlines operate everything from prop jets to 777s.

It would seem that both sides would benefit. The pilots wouldn’t be competing with pilots from other companies. The airlines would have a signal large pool of pilots which could be scheduled more efficiently than several smaller pools of pilots who are walled off from operating flights that have been contracted to different companies. Not to mention, the poor operational reliability of many regional airlines.

I'm pondering if this might happen in a few years with AA and their wholly owned regionals. Given that the rumor (or announced) info is that they're increasing pilot wages at the wholly owned regionals. I could those merging with AA at some point, but the company would want the ability to outsource some of those planes.

Now the question is, you'll still have "walled off" pilots, since there are type ratings and the like. What I'm curious if there really is enough cost in the wholly owned regionals that would be able to be cut out? There probably is some, but probably not a lot.

Merging the lists will be EPIC! See RJDC, which tried it.

docmtl wrote:

No change in Scope Clause in new United's pilot contract that would have allowed E175-E2 or else. Delta and AA will follow suit shortly:

"United was the first carrier to negotiate a new agreement with pilots. American Airlines also negotiated a new agreement, following UAL. There were no changes to Scope weights, either. UAL’s union, ALPA, only today confirmed no change to its contract. It is now highly unlikely Delta Air Lines or Alaska Airlines, whose pilots are also represented by ALPA, will change."

https://leehamnews.com

So, how will Regional Carriers deal with no new scope clause compliant regional jet to replace E1-175s after the 2027 ?

docmtl

The E1’s are brand new!! They will fly way past 2027. Ive heard the E175 is a 30+ year aircraft..

eeightning wrote:

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency, AND AT THE COST OF HIGHER NOISE LEVELS.

fixed it for you

That is an important point, the noise levels. The known issues with open rotors. There are still 3 unresolved technical issues:
https://asmedigitalcollection.asme.org/ ... n-Question

In my opinion of the challenge diffiulty
1. Blade containment. Passengers must be protected from a lost fan blade. It will happen. Hence the mass inefficient concepts of putting open rotors at the tail. The engines may be more efficient, but as the article notes the engines will weight as much as a turbofan and the packaging requires less optimal propulsion and structural placement. This takes back some of the engine gains.
2. Noise. As the link notes, open rotors can wail like a siren.
3. Diameter makes mounting a challenge. Double the problem as the easy places to place these heavy engines are prohibited by passenger safety.

Why haven't they done prototype open rotors with differing blade counts in each row? Did I miss that? We always design engines with incompatible multiples of prime numbers of blades to keep from having acoustic coupling. However, the noise is a complex enough issue that every fan concept will have to be tested early in the engine design.

Open rotors are 3 years away, at least, from launching a program. That means 11 years away from entry into service. Like the GTF engines, they will require a very long development timeline. By then, the answer on US regional fly will already be answered.

I see no scope change. By the time a new aircraft, even Embraer's turboprop enters service, most of the decisions will have been made. That is why I propose less than daily service with mainline aircraft for those airports that cannot support mainline gauge. Something will have to be done for out-station ground handling though.

Lightsaber

amcnd wrote:

docmtl wrote:

No change in Scope Clause in new United's pilot contract that would have allowed E175-E2 or else. Delta and AA will follow suit shortly:

"United was the first carrier to negotiate a new agreement with pilots. American Airlines also negotiated a new agreement, following UAL. There were no changes to Scope weights, either. UAL’s union, ALPA, only today confirmed no change to its contract. It is now highly unlikely Delta Air Lines or Alaska Airlines, whose pilots are also represented by ALPA, will change."

https://leehamnews.com

So, how will Regional Carriers deal with no new scope clause compliant regional jet to replace E1-175s after the 2027 ?

docmtl

The E1’s are brand new!! They will fly way past 2027. Ive heard the E175 is a 30+ year aircraft..

Do they meet emission standards for newly built aircraft that changes in 2027? There are some factory fresh E175s there's also some that are over 15 years old.

lightsaber wrote:

eeightning wrote:

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency, AND AT THE COST OF HIGHER NOISE LEVELS.

fixed it for you

That is an important point, the noise levels. The known issues with open rotors. There are still 3 unresolved technical issues:
https://asmedigitalcollection.asme.org/ ... n-Question

In my opinion of the challenge diffiulty
1. Blade containment. Passengers must be protected from a lost fan blade. It will happen. Hence the mass inefficient concepts of putting open rotors at the tail. The engines may be more efficient, but as the article notes the engines will weight as much as a turbofan and the packaging requires less optimal propulsion and structural placement. This takes back some of the engine gains.
2. Noise. As the link notes, open rotors can wail like a siren.
3. Diameter makes mounting a challenge. Double the problem as the easy places to place these heavy engines are prohibited by passenger safety.

Why haven't they done prototype open rotors with differing blade counts in each row? Did I miss that? We always design engines with incompatible multiples of prime numbers of blades to keep from having acoustic coupling. However, the noise is a complex enough issue that every fan concept will have to be tested early in the engine design.

Open rotors are 3 years away, at least, from launching a program. That means 11 years away from entry into service. Like the GTF engines, they will require a very long development timeline. By then, the answer on US regional fly will already be answered.

I see no scope change. By the time a new aircraft, even Embraer's turboprop enters service, most of the decisions will have been made. That is why I propose less than daily service with mainline aircraft for those airports that cannot support mainline gauge. Something will have to be done for out-station ground handling though.

Lightsaber

Safran claims noise levels on par with the CFM Leap engines

https://mentourpilot.com/safran-open-ro ... sign-leap/

JohanTally wrote:

lightsaber wrote:

eeightning wrote:

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency, AND AT THE COST OF HIGHER NOISE LEVELS.

fixed it for you

That is an important point, the noise levels. The known issues with open rotors. There are still 3 unresolved technical issues:
https://asmedigitalcollection.asme.org/ ... n-Question

In my opinion of the challenge diffiulty
1. Blade containment. Passengers must be protected from a lost fan blade. It will happen. Hence the mass inefficient concepts of putting open rotors at the tail. The engines may be more efficient, but as the article notes the engines will weight as much as a turbofan and the packaging requires less optimal propulsion and structural placement. This takes back some of the engine gains.
2. Noise. As the link notes, open rotors can wail like a siren.
3. Diameter makes mounting a challenge. Double the problem as the easy places to place these heavy engines are prohibited by passenger safety.

Why haven't they done prototype open rotors with differing blade counts in each row? Did I miss that? We always design engines with incompatible multiples of prime numbers of blades to keep from having acoustic coupling. However, the noise is a complex enough issue that every fan concept will have to be tested early in the engine design.

Open rotors are 3 years away, at least, from launching a program. That means 11 years away from entry into service. Like the GTF engines, they will require a very long development timeline. By then, the answer on US regional fly will already be answered.

I see no scope change. By the time a new aircraft, even Embraer's turboprop enters service, most of the decisions will have been made. That is why I propose less than daily service with mainline aircraft for those airports that cannot support mainline gauge. Something will have to be done for out-station ground handling though.

Lightsaber

Safran claims noise levels on par with the CFM Leap engines

https://mentourpilot.com/safran-open-ro ... sign-leap/

Fascinating read. If the noise is controlled over the entire operating range (tough and expensive to test), this is a breakthrough. Kudos. Now to launch the engine (which needs 2 to 3 years more development time) then the aircraft. What thrust range?

Lightsaber

JohanTally wrote:

lightsaber wrote:

eeightning wrote:

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency, AND AT THE COST OF HIGHER NOISE LEVELS.

fixed it for you

That is an important point, the noise levels. The known issues with open rotors. There are still 3 unresolved technical issues:
https://asmedigitalcollection.asme.org/ ... n-Question

In my opinion of the challenge diffiulty
1. Blade containment. Passengers must be protected from a lost fan blade. It will happen. Hence the mass inefficient concepts of putting open rotors at the tail. The engines may be more efficient, but as the article notes the engines will weight as much as a turbofan and the packaging requires less optimal propulsion and structural placement. This takes back some of the engine gains.
2. Noise. As the link notes, open rotors can wail like a siren.
3. Diameter makes mounting a challenge. Double the problem as the easy places to place these heavy engines are prohibited by passenger safety.

Why haven't they done prototype open rotors with differing blade counts in each row? Did I miss that? We always design engines with incompatible multiples of prime numbers of blades to keep from having acoustic coupling. However, the noise is a complex enough issue that every fan concept will have to be tested early in the engine design.

Open rotors are 3 years away, at least, from launching a program. That means 11 years away from entry into service. Like the GTF engines, they will require a very long development timeline. By then, the answer on US regional fly will already be answered.

I see no scope change. By the time a new aircraft, even Embraer's turboprop enters service, most of the decisions will have been made. That is why I propose less than daily service with mainline aircraft for those airports that cannot support mainline gauge. Something will have to be done for out-station ground handling though.

Lightsaber

Safran claims noise levels on par with the CFM Leap engines

https://mentourpilot.com/safran-open-ro ... sign-leap/

I would imagine it's sort of a "phases of flight" thing - I would imagine the E2 has the same issue with that as the A220.
The A220 on paper is quieter, but during taxi and the initial takeoff roll the engine whines and wails and vibrates so significantly that basically, everything attached to the wing box rattles uncomfortably. Try sitting over the wing, I have 3 times so far and I've noticed it twice - with AirPods in and on noise cancel mode.

It seems silly, but things like this, as well as a turboprop or anything with propellers being seen as "outdated" (which is laughable when you compare the Q400 with say, an early CRJ) and you can see it in passenger experience scores specifically in the US - I'm sure the trend is universal but it is certainly very pronounced here. Now stick two rearward-facing contra-rotating propellers that look scary as heck on each wing, it's gonna land with the public as well as a flying potato.

I think the predictions of the death of the regional airline are, as they have been previously, a bit overblown. There are still Skywest and Envoy lifers (god I don't know why), Mesa is a cockroach that will outlive them all, and we'll see how AA throwing money at the problem with Piedmont and PSA influences Delta's future with Endeavor. Air Wisconsin is just f'd.
So no, maybe they don't get scope relief, and maybe we never see the E2 in a major US airline's colors, but the E175s bouncing around the whole country with their funky new winglets and weird nose-high taxi still have a lot of life left in them. They've clearly worked quite well for United in testing and proving new route opportunities out of DEN.

There's still a market and still demand, so if in 5 years they have to start charging $600 for a 90 mile flight on a 15 year old E175 because labor costs to keep pilots, flight attendants, airport ops and ground ops personnel have skyrocketed, they will. The 50 seat RJ is a fundamentally dead concept though, and it has had a clear exit from the market since the E170 and CRJ7 were adopted in large numbers.

Ultimately I would imagine they'd do better with new frames and making the labor concessions necessary to get them on property... but that's not how airlines think when it comes to labor relations.

lightsaber wrote:

JohanTally wrote:

lightsaber wrote:

That is an important point, the noise levels. The known issues with open rotors. There are still 3 unresolved technical issues:
https://asmedigitalcollection.asme.org/ ... n-Question

In my opinion of the challenge diffiulty
1. Blade containment. Passengers must be protected from a lost fan blade. It will happen. Hence the mass inefficient concepts of putting open rotors at the tail. The engines may be more efficient, but as the article notes the engines will weight as much as a turbofan and the packaging requires less optimal propulsion and structural placement. This takes back some of the engine gains.
2. Noise. As the link notes, open rotors can wail like a siren.
3. Diameter makes mounting a challenge. Double the problem as the easy places to place these heavy engines are prohibited by passenger safety.

Why haven't they done prototype open rotors with differing blade counts in each row? Did I miss that? We always design engines with incompatible multiples of prime numbers of blades to keep from having acoustic coupling. However, the noise is a complex enough issue that every fan concept will have to be tested early in the engine design.

Open rotors are 3 years away, at least, from launching a program. That means 11 years away from entry into service. Like the GTF engines, they will require a very long development timeline. By then, the answer on US regional fly will already be answered.

I see no scope change. By the time a new aircraft, even Embraer's turboprop enters service, most of the decisions will have been made. That is why I propose less than daily service with mainline aircraft for those airports that cannot support mainline gauge. Something will have to be done for out-station ground handling though.

Lightsaber

Safran claims noise levels on par with the CFM Leap engines

https://mentourpilot.com/safran-open-ro ... sign-leap/

Fascinating read. If the noise is controlled over the entire operating range (tough and expensive to test), this is a breakthrough. Kudos. Now to launch the engine (which needs 2 to 3 years more development time) then the aircraft. What thrust range?

Lightsaber

The originally proposed Embraer E3 with rear turboprops and a T-tail would be a great candidate IMHO. It's fuselage is based on other E-jets so it would easily integrate and already needs strengthening for the potential blade failure.

bluecrew wrote:

JohanTally wrote:

lightsaber wrote:

That is an important point, the noise levels. The known issues with open rotors. There are still 3 unresolved technical issues:
https://asmedigitalcollection.asme.org/ ... n-Question

In my opinion of the challenge diffiulty
1. Blade containment. Passengers must be protected from a lost fan blade. It will happen. Hence the mass inefficient concepts of putting open rotors at the tail. The engines may be more efficient, but as the article notes the engines will weight as much as a turbofan and the packaging requires less optimal propulsion and structural placement. This takes back some of the engine gains.
2. Noise. As the link notes, open rotors can wail like a siren.
3. Diameter makes mounting a challenge. Double the problem as the easy places to place these heavy engines are prohibited by passenger safety.

Why haven't they done prototype open rotors with differing blade counts in each row? Did I miss that? We always design engines with incompatible multiples of prime numbers of blades to keep from having acoustic coupling. However, the noise is a complex enough issue that every fan concept will have to be tested early in the engine design.

Open rotors are 3 years away, at least, from launching a program. That means 11 years away from entry into service. Like the GTF engines, they will require a very long development timeline. By then, the answer on US regional fly will already be answered.

I see no scope change. By the time a new aircraft, even Embraer's turboprop enters service, most of the decisions will have been made. That is why I propose less than daily service with mainline aircraft for those airports that cannot support mainline gauge. Something will have to be done for out-station ground handling though.

Lightsaber

Safran claims noise levels on par with the CFM Leap engines

https://mentourpilot.com/safran-open-ro ... sign-leap/

I would imagine it's sort of a "phases of flight" thing - I would imagine the E2 has the same issue with that as the A220.
The A220 on paper is quieter, but during taxi and the initial takeoff roll the engine whines and wails and vibrates so significantly that basically, everything attached to the wing box rattles uncomfortably. Try sitting over the wing, I have 3 times so far and I've noticed it twice - with AirPods in and on noise cancel mode.

It seems silly, but things like this, as well as a turboprop or anything with propellers being seen as "outdated" (which is laughable when you compare the Q400 with say, an early CRJ) and you can see it in passenger experience scores specifically in the US - I'm sure the trend is universal but it is certainly very pronounced here. Now stick two rearward-facing contra-rotating propellers that look scary as heck on each wing, it's gonna land with the public as well as a flying potato.

I think the predictions of the death of the regional airline are, as they have been previously, a bit overblown. There are still Skywest and Envoy lifers (god I don't know why), Mesa is a cockroach that will outlive them all, and we'll see how AA throwing money at the problem with Piedmont and PSA influences Delta's future with Endeavor. Air Wisconsin is just f'd.
So no, maybe they don't get scope relief, and maybe we never see the E2 in a major US airline's colors, but the E175s bouncing around the whole country with their funky new winglets and weird nose-high taxi still have a lot of life left in them. They've clearly worked quite well for United in testing and proving new route opportunities out of DEN.

There's still a market and still demand, so if in 5 years they have to start charging $600 for a 90 mile flight on a 15 year old E175 because labor costs to keep pilots, flight attendants, airport ops and ground ops personnel have skyrocketed, they will. The 50 seat RJ is a fundamentally dead concept though, and it has had a clear exit from the market since the E170 and CRJ7 were adopted in large numbers.

Ultimately I would imagine they'd do better with new frames and making the labor concessions necessary to get them on property... but that's not how airlines think when it comes to labor relations.

Their is nothing to the advantage of the pilot's unions to allow more RJ flying. There is much regret they allowed as much as they have. This won't be a fast atrophy; but the cost per passenger has increased and less than daily flights work. Quite well.

It won't be a fast process. Some will accept turboprops. Most will be willing to drive two hours or take one of the airline branded buses.

What the airlines need to do is work on the partial weekly and airline branded buses. Will some turboprops be accepted? Yes. Will some additional E1-175 be bought? Yes.

We've debated scope increase ever since the MRJ and E2-175 were launch and... there is a reason for no progress. The concessions required are more costly than going to less than daily service or buses.

https://wusfnews.wusf.usf.edu/2022-04-1 ... ort-routes
DAVID SCHAPER, BYLINE: When taking American Airlines' new service from Atlantic City, N.J., or Allentown, Pa., to any destination connecting through the airline's Philadelphia hub, you'll arrive at the small regional airport like you would for any other flight. You'll check in and check your bags at the kiosk and counter, go through the security checkpoint, and as you board, you'll see the American Airlines logo and color scheme. But what you won't see are wings because this flight is on a bus.


I fully expect fuel to eventually go back down in price, but to be more expensive than it was for a long time. The spot price for US aviation fuel is now $4.079 per gallon. Or $1,352.21 per metric ton of jet fuel. https://globaloilandgastrading.com/avia ... tric%20Ton
or in chart form, source: https://www.eia.gov/dnav/pet/hist/EER_E ... C_DPGD.htm

With the demand to go to SAF, I do not expect $2/gallon (call it about $600/metric ton) jet fuel to return. This puts pressure to upgauge too.

There is no E2-175 without scope relief. I'm not seeing the pilot unions and legacy airlines coming to agreement. What I do see is Allegiant, Frontier, Spirit, and Breeze sniping away at the US regional market. Since less than daily works for them, why not Delta, United, and American? I do not see $600 for that 90 minute flight. I see $150 (or less) for a 150 minute (or less) bus trip. Those willing to pay $600 will fly on 9 seaters.

The issue is pilots. More specifically ATP or 1500 hour rule to be experienced enough to fly into congested airspace.

We already know Delta is retiring their 50 seat CRJs in 18 months:
https://onemileatatime.com/delta-retiring-crj-717-767/

I do not see an end to regional flying, but rather a substitution for at least half the service.

Lightsaber

lightsaber wrote:

eeightning wrote:

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency, AND AT THE COST OF HIGHER NOISE LEVELS.

fixed it for you

That is an important point, the noise levels. The known issues with open rotors. There are still 3 unresolved technical issues:
https://asmedigitalcollection.asme.org/ ... n-Question

In my opinion of the challenge diffiulty
1. Blade containment. Passengers must be protected from a lost fan blade. It will happen. Hence the mass inefficient concepts of putting open rotors at the tail. The engines may be more efficient, but as the article notes the engines will weight as much as a turbofan and the packaging requires less optimal propulsion and structural placement. This takes back some of the engine gains.
2. Noise. As the link notes, open rotors can wail like a siren.
3. Diameter makes mounting a challenge. Double the problem as the easy places to place these heavy engines are prohibited by passenger safety.

Why haven't they done prototype open rotors with differing blade counts in each row? Did I miss that? We always design engines with incompatible multiples of prime numbers of blades to keep from having acoustic coupling. However, the noise is a complex enough issue that every fan concept will have to be tested early in the engine design.

Open rotors are 3 years away, at least, from launching a program. That means 11 years away from entry into service. Like the GTF engines, they will require a very long development timeline. By then, the answer on US regional fly will already be answered.

I see no scope change. By the time a new aircraft, even Embraer's turboprop enters service, most of the decisions will have been made. That is why I propose less than daily service with mainline aircraft for those airports that cannot support mainline gauge. Something will have to be done for out-station ground handling though.

Lightsaber

I politely wonder if you're wrong.

It seems an engine maker could offer a turbo prop engine with a smaller, more bladed, faster spinning propeller. And call it a propeller. And get it certified under propeller rules. Which do not require blade containement and such.

Certainly one can certify an 8 blade prop as a propeller.

kitplane01 wrote:

lightsaber wrote:

eeightning wrote:

Difference between open rotor and turboprop, is the speed range possible for the rotor is much higher than for a prop. By using rotor technologies without the enclosure, the rotor diameter can be expanded while both rotational and forward speed are enhanced, without loss of fuel efficiency, AND AT THE COST OF HIGHER NOISE LEVELS.

fixed it for you

That is an important point, the noise levels. The known issues with open rotors. There are still 3 unresolved technical issues:
https://asmedigitalcollection.asme.org/ ... n-Question

In my opinion of the challenge diffiulty
1. Blade containment. Passengers must be protected from a lost fan blade. It will happen. Hence the mass inefficient concepts of putting open rotors at the tail. The engines may be more efficient, but as the article notes the engines will weight as much as a turbofan and the packaging requires less optimal propulsion and structural placement. This takes back some of the engine gains.
2. Noise. As the link notes, open rotors can wail like a siren.
3. Diameter makes mounting a challenge. Double the problem as the easy places to place these heavy engines are prohibited by passenger safety.

Why haven't they done prototype open rotors with differing blade counts in each row? Did I miss that? We always design engines with incompatible multiples of prime numbers of blades to keep from having acoustic coupling. However, the noise is a complex enough issue that every fan concept will have to be tested early in the engine design.

Open rotors are 3 years away, at least, from launching a program. That means 11 years away from entry into service. Like the GTF engines, they will require a very long development timeline. By then, the answer on US regional fly will already be answered.

I see no scope change. By the time a new aircraft, even Embraer's turboprop enters service, most of the decisions will have been made. That is why I propose less than daily service with mainline aircraft for those airports that cannot support mainline gauge. Something will have to be done for out-station ground handling though.

Lightsaber

I politely wonder if you're wrong.

It seems an engine maker could offer a turbo prop engine with a smaller, more bladed, faster spinning propeller. And call it a propeller. And get it certified under propeller rules. Which do not require blade containement and such.

Certainly one can certify an 8 blade prop as a propeller.

Pratt still has PW4000 engines grounded due to fan blade containment failure:
https://aviationweek.com/air-transport/ ... blade-loss

Could a larger propeller be certified? Yes. The first blade out event would ground the type. The reasons turboprops are not grounded is the relative stress at the propellers root is low enough to ensure finding failures far before a blade out event. The higher mach numbers of open rotors ensure more blade stress. Turbofans mitigate that risk by shroud fan blade protection. Pratt failing that resulted in their 777 engines being grounded. If a turboprop has a blade failure risk that exceeds FAA or EASA safety guidelines, it to will be grounded. Hence why the mitigation of off engine mounting locations.

I'd love to be proven wrong. But propfans will have higher stress on the fan blades (as would a higher rpm turboprop). If the risk of ice, bird strike, FOD, or fatigue failure becomes too high, as there certainly is in turbofan engines, some form of mitigation must occur.

The FAA/EASA have shown with the MAX and Pratt 777s, they will ground whole types over excessive risk. Propfans will mitigate the risk, but that takes years of R&D.

However, for this thread a moot point. There will not be an open rotors aircraft within to the next decade, there is just too much tech to develop. Heck, Embraer needs more time to develop to their turboprop concept.

The fate of US regional flying will be determined on the currently available aircraft. The window to develop a new type before the fuel regulation changes has passed, even for a new turboprop. I expect no scope change and the economics of regional flying is so marginal, only a well optimized airframe will thrive.

That doesn't mean no possible regional solution. Airline branded buses and less than daily service on larger narrowbody aircraft can fill most of the niche, in my opinion.

In 18 months when Delta cuts 50 seat service (link above on CR2 retirement) is when we see the transition. This isn't some academic discussion anymore; there will be a huge industry shift with DL's 50 seater retirement. In 5.5 years with the tightening fuel burn requirements, another shift.

I see no reason buses and less than daily service couldn't fill the need.

Lightsaber

" ....If a market is too small to be able to support 2x mainline aircraft a day, its probably too small to be worth serving at all. ..."

Scope clauses, by some readings (mine?) are blatant restrictions of trade that is somehow demanded by powerful unions. (I speak as a lifelong union member, currently currently on withdrawal). I support living standards for regional air service. Moderately higher wages, and an end of the insane scheduling some of them face. FAA does have a charge to promote aviation, and that should include affordable and workable access to the national network. One way would be some sort of required interlining with smaller planes flying to existing regional airports. Buses, vans*, and even trains can and should be part of the solution. But so should planes carrying fifty people and less to larger airports and hence connections medical facilites and the rest of the world.

* licensing, insurance, certifications are all expensive barriers to better service. Federal and local government should consider funding these.

I really think the pilot unions are approaching the whole scope clause issue from the wrong angle. They focus on limiting the number of seats and MTOWs of regional jets, but they ignore the fact that the big airlines are using 76 and even 50-seaters to perform trunk routes, some exceeding 1,000nm.

For example, Envoy flies E145s for American Eagle on the ORD-YYZ, ORD-YUL, ORD-CVG, ORD-DTW and ORD-MSP routes. SkyWest flies E175s for Delta Connection on routes such as SLC-IAH, SLC-ORD, SLC-LAX, SLC-SEA, et. al. These are routes that should easily support mainline ops, but in the name of capacity optimization, cost reduction & adding frequencies to their hubs, the parent airlines use their regionals instead.

[code][/code]

FLALEFTY wrote:

I really think the pilot unions are approaching the whole scope clause issue from the wrong angle. They focus on limiting the number of seats and MTOWs of regional jets, but they ignore the fact that the big airlines are using 76 and even 50-seaters to perform trunk routes, some exceeding 1,000nm.

For example, Envoy flies E145s for American Eagle on the ORD-YYZ, ORD-YUL, ORD-CVG, ORD-DTW and ORD-MSP routes. SkyWest flies E175s for Delta Connection on routes such as SLC-IAH, SLC-ORD, SLC-LAX, SLC-SEA, et. al. These are routes that should easily support mainline ops, but in the name of capacity optimization, cost reduction & adding frequencies to their hubs, the parent airlines use their regionals instead.

Isn’t that a key part of regional jets? Providing frequency throughout the day to give passengers options?

FLALEFTY wrote:

I really think the pilot unions are approaching the whole scope clause issue from the wrong angle. They focus on limiting the number of seats and MTOWs of regional jets, but they ignore the fact that the big airlines are using 76 and even 50-seaters to perform trunk routes, some exceeding 1,000nm.

For example, Envoy flies E145s for American Eagle on the ORD-YYZ, ORD-YUL, ORD-CVG, ORD-DTW and ORD-MSP routes. SkyWest flies E175s for Delta Connection on routes such as SLC-IAH, SLC-ORD, SLC-LAX, SLC-SEA, et. al. These are routes that should easily support mainline ops, but in the name of capacity optimization, cost reduction & adding frequencies to their hubs, the parent airlines use their regionals instead.

Not quite true at UAL at least. There are restrictions on mileage, percentages of hub to hub flying, and percentages on designated cities that United Express must comply with in addition to the passenger and weight limits.

1-C-1-b At least eighty percent (80%) of all United Express Flights each month shall be under 900 statute miles.

1-C-1-d Hubs In any Rolling Twelve-Month Period, the number of block hours of United Express Flying operated by United Express Carriers as a group non-stop between current or future Company Hubs may not exceed five percent (5%) of all United Express Flying as a percentage of the total block hours of United Express Flying. A pair of Flights by a United Express Carrier operated under a single flight number in which one Flight is scheduled to originate at a Company Hub and the second Flight is scheduled to terminate at a second Company Hub shall be included within the five percent (5%) limitation, unless the Company imposes an IATA Standard Schedules Information Manual Type “A” Traffic Restriction Code on the through itinerary that shall suppress the display of such itinerary.

1-C-1-e Connecting Operations United Express Carriers as a group shall Schedule at least ninety percent (90%) of their United Express Flying Non-Stops into or out of the following airports: IAD, DCA, MIA, LGA, EWR, JFK, ORD, DEN, LAX, SFO, SEA, BOS, PDX, PHX, LAS, SJC, SAN, IAH, CLE, GUM, any airport within thirty (30) statute miles of any of the foregoing, any other airport with fifty (50) or more scheduled daily departures of Company Flying, and any other airport that the parties later agree to add to this list. Up to five percent (5%) of United Express Flying flights may be applied toward satisfying this requirement even if such flights include multiple stops, as long as such flights i) originate or terminate at one of the foregoing airports, ii) maintain a single flight number on a single aircraft for all the legs of such flight to or from such airport, and iii) operate with scheduled intermediate stops of less than two (2) hours

Like anything when dealing with contracts, its what you negotiate, and what both sides agree upon. (and not just for union contracts. What about purchasing a home or a car? The buyer and seller have to come to an agreement)

jbs2886 wrote:

docmtl wrote:

No change in Scope Clause in new United's pilot contract that would have allowed E175-E2 or else. Delta and AA will follow suit shortly:

"United was the first carrier to negotiate a new agreement with pilots. American Airlines also negotiated a new agreement, following UAL. There were no changes to Scope weights, either. UAL’s union, ALPA, only today confirmed no change to its contract. It is now highly unlikely Delta Air Lines or Alaska Airlines, whose pilots are also represented by ALPA, will change."

https://leehamnews.com

So, how will Regional Carriers deal with no new scope clause compliant regional jet to replace E1-175s after the 2027 ?

docmtl

Well, AS doesn’t have a scope clause…so this is questionable.

This is another reason why I always thought AS was prime for obtaining the E2. They're getting rid of the Q400 (at QX), and they already operate the E1. Seems like a somewhat no-brainer move in efficiency.

ikolkyo wrote:

[code][/code]

FLALEFTY wrote:

I really think the pilot unions are approaching the whole scope clause issue from the wrong angle. They focus on limiting the number of seats and MTOWs of regional jets, but they ignore the fact that the big airlines are using 76 and even 50-seaters to perform trunk routes, some exceeding 1,000nm.

For example, Envoy flies E145s for American Eagle on the ORD-YYZ, ORD-YUL, ORD-CVG, ORD-DTW and ORD-MSP routes. SkyWest flies E175s for Delta Connection on routes such as SLC-IAH, SLC-ORD, SLC-LAX, SLC-SEA, et. al. These are routes that should easily support mainline ops, but in the name of capacity optimization, cost reduction & adding frequencies to their hubs, the parent airlines use their regionals instead.

Isn’t that a key part of regional jets? Providing frequency throughout the day to give passengers options?

However, hub-to-hub and hub raiding missions are the sort of routes that should be mainline. In Delta's case, SLC is one of their largest bases for their A220s and one of the reasons they bought them was to operate these sort of routes.

EssentialBusDC wrote:

Not quite true at UAL at least. There are restrictions on mileage, percentages of hub to hub flying, and percentages on designated cities that United Express must comply with in addition to the passenger and weight limits.

It is good that United is doing the right thing and limiting the stage lengths on regional routes, as well limiting hub-to-hub flying by their regionals. I wish the other three legacies (Delta, American & Alaska) would do likewise.

superbizzy73 wrote:

jbs2886 wrote:

docmtl wrote:

No change in Scope Clause in new United's pilot contract that would have allowed E175-E2 or else. Delta and AA will follow suit shortly:

"United was the first carrier to negotiate a new agreement with pilots. American Airlines also negotiated a new agreement, following UAL. There were no changes to Scope weights, either. UAL’s union, ALPA, only today confirmed no change to its contract. It is now highly unlikely Delta Air Lines or Alaska Airlines, whose pilots are also represented by ALPA, will change."

https://leehamnews.com

So, how will Regional Carriers deal with no new scope clause compliant regional jet to replace E1-175s after the 2027 ?

docmtl

Well, AS doesn’t have a scope clause…so this is questionable.

This is another reason why I always thought AS was prime for obtaining the E2. They're getting rid of the Q400 (at QX), and they already operate the E1. Seems like a somewhat no-brainer move in efficiency.

Unfortunately for Embraer, the E175E2 only has 6% better fuel efficiency than the E1 due to its over 5t higher weight and additional aerodynamic drag caused by the higher bypass engines. Throw in the higher book prices for the E175E2 and it will likely take years of service to see a financial advantage for any airline. Also, Embraer has put this aircraft's test & certification program on hold until 2024 and even then the restart will be contingent on receiving firm orders for the type (currently there are none).

FLALEFTY wrote:

superbizzy73 wrote:

jbs2886 wrote:

Well, AS doesn’t have a scope clause…so this is questionable.

This is another reason why I always thought AS was prime for obtaining the E2. They're getting rid of the Q400 (at QX), and they already operate the E1. Seems like a somewhat no-brainer move in efficiency.

Unfortunately for Embraer, the E175E2 only has 6% better fuel efficiency than the E1 due to its over 5t higher weight and additional aerodynamic drag caused by the higher bypass engines. Throw in the higher book prices for the E175E2 and it will likely take years of service to see a financial advantage for any airline. Also, Embraer has put this aircraft's test & certification program on hold until 2024 and even then the restart will be contingent on receiving firm orders for the type (currently there are none).

Oddly enough, the E1 may have higher resell value.

bluecrew wrote:

There are still Skywest and Envoy lifers (god I don't know why), Mesa is a cockroach that will outlive them all, and we'll see how AA throwing money at the problem with Piedmont and PSA influences Delta's future with Endeavor. Air Wisconsin is just f'd.

It's not hard to understand why OO/MQ/etc. have lifers. If you own a house in-base, have a spouse who doesn't want to relocate, don't want to uproot your kids from their schools/friends, have family in-base, etc. it may be very unattractive to go back to commuting to some expensive hub city like NYC/LAX/SFO/BOS/MIA/ORD/WAS to sit reserve in a crash pad for less money after expenses. Even when you get off reserve, you're still going to have a line in some place you have to commute to. If you're much over 40, it's probably just not worth giving up the quality of life of living in-base, being home most nights, and having holidays off for not as many years of higher earning potential.

And every time ZW seems to be done for, they still manage to pull a rabbit out of a hat. I don't know how they're still going but then again it took a lot to finally put Great Lakes out of our collective misery.

FLALEFTY wrote:

I really think the pilot unions are approaching the whole scope clause issue from the wrong angle. They focus on limiting the number of seats and MTOWs of regional jets, but they ignore the fact that the big airlines are using 76 and even 50-seaters to perform trunk routes, some exceeding 1,000nm.

I think the most important focus for the pilot unions ought to be limiting the overall ratio of regional flying vs. mainline in their respective airline networks. It shouldn't matter if a RJ flies ORD-MSP if that frees up mainline aircraft for other markets. As long as mainline pilot work grows more rapidly than the outsourced jobs, it's still a win for the mainline pilots for career growth.

superbizzy73 wrote:

This is another reason why I always thought AS was prime for obtaining the E2. They're getting rid of the Q400 (at QX), and they already operate the E1. Seems like a somewhat no-brainer move in efficiency.

I don't think AS wants to be the sole U.S. operator of a relatively modest fleet of E2s. It's probably not helpful that the E175-E2 hasn't sold at all globally -- it becomes incredibly difficult to find a new home for those planes if your fleet requirements change.

FLALEFTY wrote:

Unfortunately for Embraer, the E175E2 only has 6% better fuel efficiency than the E1 due to its over 5t higher weight and additional aerodynamic drag caused by the higher bypass engines. Throw in the higher book prices for the E175E2 and it will likely take years of service to see a financial advantage for any airline.

Also add the costs across the mainline network of whatever concession(s) the airline must make to the pilots in order to get scope relief for the E175-E2...

lightsaber wrote:

kitplane01 wrote:

lightsaber wrote:

That is an important point, the noise levels. The known issues with open rotors. There are still 3 unresolved technical issues:
https://asmedigitalcollection.asme.org/ ... n-Question

In my opinion of the challenge diffiulty
1. Blade containment. Passengers must be protected from a lost fan blade. It will happen. Hence the mass inefficient concepts of putting open rotors at the tail. The engines may be more efficient, but as the article notes the engines will weight as much as a turbofan and the packaging requires less optimal propulsion and structural placement. This takes back some of the engine gains.
2. Noise. As the link notes, open rotors can wail like a siren.
3. Diameter makes mounting a challenge. Double the problem as the easy places to place these heavy engines are prohibited by passenger safety.

Why haven't they done prototype open rotors with differing blade counts in each row? Did I miss that? We always design engines with incompatible multiples of prime numbers of blades to keep from having acoustic coupling. However, the noise is a complex enough issue that every fan concept will have to be tested early in the engine design.

Open rotors are 3 years away, at least, from launching a program. That means 11 years away from entry into service. Like the GTF engines, they will require a very long development timeline. By then, the answer on US regional fly will already be answered.

I see no scope change. By the time a new aircraft, even Embraer's turboprop enters service, most of the decisions will have been made. That is why I propose less than daily service with mainline aircraft for those airports that cannot support mainline gauge. Something will have to be done for out-station ground handling though.

Lightsaber

I politely wonder if you're wrong.

It seems an engine maker could offer a turbo prop engine with a smaller, more bladed, faster spinning propeller. And call it a propeller. And get it certified under propeller rules. Which do not require blade containement and such.

Certainly one can certify an 8 blade prop as a propeller.

Pratt still has PW4000 engines grounded due to fan blade containment failure:
https://aviationweek.com/air-transport/ ... blade-loss

Could a larger propeller be certified? Yes. The first blade out event would ground the type. The reasons turboprops are not grounded is the relative stress at the propellers root is low enough to ensure finding failures far before a blade out event. The higher mach numbers of open rotors ensure more blade stress. Turbofans mitigate that risk by shroud fan blade protection. Pratt failing that resulted in their 777 engines being grounded. If a turboprop has a blade failure risk that exceeds FAA or EASA safety guidelines, it to will be grounded. Hence why the mitigation of off engine mounting locations.

I'd love to be proven wrong. But propfans will have higher stress on the fan blades (as would a higher rpm turboprop). If the risk of ice, bird strike, FOD, or fatigue failure becomes too high, as there certainly is in turbofan engines, some form of mitigation must occur.

The FAA/EASA have shown with the MAX and Pratt 777s, they will ground whole types over excessive risk. Propfans will mitigate the risk, but that takes years of R&D.

However, for this thread a moot point. There will not be an open rotors aircraft within to the next decade, there is just too much tech to develop. Heck, Embraer needs more time to develop to their turboprop concept.

The fate of US regional flying will be determined on the currently available aircraft. The window to develop a new type before the fuel regulation changes has passed, even for a new turboprop. I expect no scope change and the economics of regional flying is so marginal, only a well optimized airframe will thrive.

That doesn't mean no possible regional solution. Airline branded buses and less than daily service on larger narrowbody aircraft can fill most of the niche, in my opinion.

In 18 months when Delta cuts 50 seat service (link above on CR2 retirement) is when we see the transition. This isn't some academic discussion anymore; there will be a huge industry shift with DL's 50 seater retirement. In 5.5 years with the tightening fuel burn requirements, another shift.

I see no reason buses and less than daily service couldn't fill the need.

Lightsaber

Any airline that goes to less than daily service at smaller airports will essentially be writing off the vast a majority of business travelers at those airports. This will cause revenue to crater and make the routes unprofitable. Business travelers need a minimum level of daily weekday service (ideally 2x or 3x daily), and preferably options to more than one hub to make an airline their preferred choice. With the growth in travel demand and 76 jet flying staying steady for the foreseeable future, there are very few airports that will need to go to less than daily service, which as I stated above is for leisure travelers only. Since Allegiant and some small start ups like Breeze already serve the less than daily leisure market, I just don't see anything less than weekday daily from the big 3 anytime soon.

FLALEFTY wrote:

I really think the pilot unions are approaching the whole scope clause issue from the wrong angle. They focus on limiting the number of seats and MTOWs of regional jets...

That's not correct. Rather, the unions are quite OK with the airlines operating more of these aircraft as long as the pilots from the major fly them.

ScottB wrote:

I think the most important focus for the pilot unions ought to be limiting the overall ratio of regional flying vs. mainline in their respective airline networks. It shouldn't matter if a RJ flies ORD-MSP if that frees up mainline aircraft for other markets. As long as mainline pilot work grows more rapidly than the outsourced jobs, it's still a win for the mainline pilots for career growth.

Under Smisek, CO>UA began operating ERJ-145s between ATL and EWR. DL flew mainline jets. Guess which the customers preferred?

In other words, there are places where the RJ is appropriate and places that it is not.

Velocirapture wrote:

FLALEFTY wrote:

I really think the pilot unions are approaching the whole scope clause issue from the wrong angle. They focus on limiting the number of seats and MTOWs of regional jets...

That's not correct. Rather, the unions are quite OK with the airlines operating more of these aircraft as long as the pilots from the major fly them.

especially since UAALPA has had the pilot pay scales in place for every UAX fleet model for over 10 years. AND? they could pull the trigger Tomorrow if UAL agreed to do it! they have No reason to hinder UAL about it. This is a matter of "business"..

Velocirapture wrote:

FLALEFTY wrote:

I really think the pilot unions are approaching the whole scope clause issue from the wrong angle. They focus on limiting the number of seats and MTOWs of regional jets...

That's not correct. Rather, the unions are quite OK with the airlines operating more of these aircraft as long as the pilots from the major fly them.

I get a giggle when someone takes a small part of a post out of context, spins it to fit their agenda and declares it to be "not correct".

Now as for your comment, it has been stated before by the major airlines that due to higher labor costs they cannot use mainline pilots & crews to support flying 50~76 seat regional jets. What the major airline unions said about their willingness to fly regional jets is just a fantasy. Or as they say in the South, "That dog won't hunt".

strfyr51 wrote:

especially since UAALPA has had the pilot pay scales in place for every UAX fleet model for over 10 years. AND? they could pull the trigger Tomorrow if UAL agreed to do it! they have No reason to hinder UAL about it. This is a matter of "business"..

It is simple, UAL farms the 50~76 seat regional jets to contractors because they are substantially cheaper when it comes to labor costs.

Quick scope question: Are there large-ish airlines with either no union, or no scope clause? And do these airlines have a significant competetive advantage of scope-clause airlines?

kitplane01 wrote:

Quick scope question: Are there large-ish airlines with either no union, or no scope clause? And do these airlines have a significant competetive advantage of scope-clause airlines?

Alaska Airlines doesn't have a scope clause.

I'm not sure if that gives the an advantage or not. Management isn't stupid enough to try putting 737s at their wholly owned regional operator Horizon (QX), and I don't think Skywest could operate a 737 given their operations with other major carriers. I also don't think putting the E190 at QX is worth the hassle for a plane that is just a bit smaller than the 737-700. The pilots of course would like a scope clause and rattling them in those ways might force the company's hand in negotiations.

Edit: Also FWIW, for US airlines that have a regional operations, Alaska has the lowest percentage of planes operated in the regional side at 29.9%. (For comparison AA: 38.8%, DL: 30.9%, UA: 39.8%)

FLALEFTY wrote:

Now as for your comment, it has been stated before by the major airlines that due to higher labor costs they cannot use mainline pilots & crews to support flying 50~76 seat regional jets. What the major airline unions said about their willingness to fly regional jets is just a fantasy. Or as they say in the South, "That dog won't hunt".

It is simple, UAL farms the 50~76 seat regional jets to contractors because they are substantially cheaper when it comes to labor costs.

Prior to regional jets UA flew a fleet of 100-125 seaters. UA had over 400 mainline departures from ORD.

Now it is more economical to operate 75 seaters with low wage crew than small mainline aircraft. UA had 260 mainline departures at ORD in 2019.

I'm curious if any of US3 has disclosed how much it would cost them to bring their regional ops under their mainline operations. I'm really curious about AA specifically because they have the largest wholly-owned regional ops

Time for the regionals to order up some E175E1s. I think they will be valuable as the 2030s pass and no replacement is launched. The pace of aircraft development looks like it is becoming the inverse of Moore's law for semiconductor chips.

As a United pilot, I want to see the 175's that we own flown by our pilots. I held the same view as a regional pilot. No waivers on scope and work to make it advantageous for all parties to have us fly them.

airtran737 wrote:

As a United pilot, I want to see the 175's that we own flown by our pilots. I held the same view as a regional pilot. No waivers on scope and work to make it advantageous for all parties to have us fly them.

I guess the question is are you willing to have the 175s flown for say.. 2/3 of the 737 rate? (Or something lesser than the mainline narrowbodies?)