Search found 2601 matches

by RJMAZ
Fri Sep 15, 2017 10:43 am
Forum: Civil Aviation
Topic: What will the Boeing MOM do for the industry?
Replies: 78
Views: 11010

Re: What will the Boeing MOM do for the industry?

Frame with lowest trip cost in its class wins the race. Sure it is more difficult to design, but adding more seats is not the solution. CASM is good on brochure not in real world. Half empty A380 is no good if your competitor is flying full B787. So all the 737/A320 flights should be replaced with ...

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by RJMAZ
Wed Sep 13, 2017 11:12 pm
Forum: Civil Aviation
Topic: What will the Boeing MOM do for the industry?
Replies: 78
Views: 11010

Re: What will the Boeing MOM do for the industry?

If it wont open new routes it wont be launched. Boeing is looking to offer a plane that makes money for its customers and new routes are a good recipe to do this. And Boeing have a track record of doing just this. Reducing CASM is also a recipe to make airlines money. Boeing has a track record at p...

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by RJMAZ
Wed Sep 13, 2017 2:26 pm
Forum: Civil Aviation
Topic: What will the Boeing MOM do for the industry?
Replies: 78
Views: 11010

Re: What will the Boeing MOM do for the industry?

Isn't it unfair to say a similarly sized aircraft to the 762 will have the same fate when in fact the 762 didn't sell as well (mainly?) because it was the shortest of 767 models? And we all know short models don't sell very well (a338, 736, 788, a318, etc.). The reason the shrinks didn't sell becau...

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by RJMAZ
Wed Sep 13, 2017 1:19 pm
Forum: Civil Aviation
Topic: What will the Boeing MOM do for the industry?
Replies: 78
Views: 11010

Re: What will the Boeing MOM do for the industry?

That works both ways: Stifling too much range and performance, for the sake of efficiency, has been the bane of several models... 764ER, 739A, etc etc. This proves my point. 764 with 7 abreast had worse CASM than the larger 8 abreast A330 and 9 abreast 777. Thats why it didn't sell. The 739 with fu...

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by RJMAZ
Wed Sep 13, 2017 1:36 am
Forum: Civil Aviation
Topic: What will the Boeing MOM do for the industry?
Replies: 78
Views: 11010

Re: What will the Boeing MOM do for the industry?

I personally think the aircraft won't open up any new routes. It will simply up size existing narrow body routes. My analysis predicts the MOMs main objective will be to have superior CASM to the 737 and A321 on all flights. Range will be at the very most 20% greater than the 737 and A321 so it's ju...

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by RJMAZ
Thu Aug 31, 2017 3:48 am
Forum: Civil Aviation
Topic: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus
Replies: 48
Views: 8748

Re: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus

I'm assuming with your second option that it's cheaper to make the stop in Anchorage rather than fly from Seattle/Portland straight to Japan/Korea with something like a 787? Good point. No one will pick the one stop option in Anchorage on a MOM aircraft. They will simply fly direct with the a 787. ...

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by RJMAZ
Thu Aug 31, 2017 12:24 am
Forum: Civil Aviation
Topic: Boeing 787 as starting point Large NMA / MoM, unlikely?
Replies: 110
Views: 17949

Re: Boeing 787 as starting point Large NMA / MoM, unlikely?

Boeing has to do something when the 787-8 orders end in a few years time. I agree with kessje that removing 20T from the 787-8 would be extremely easy. That is only 16% reduction in weight. The people who disagree should look up the size and weights of the Airbus A300. It is 30% lighter than the 78...

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by RJMAZ
Wed Aug 30, 2017 8:01 am
Forum: Civil Aviation
Topic: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus
Replies: 48
Views: 8748

Re: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus

With the CS100 and CS300 for example they have a CASM advantage. For them to break into a new market they need even greater CASM advantage than normal to offset the risk of say high maintenance or poor support. This explains the poor but acceptable sales. If it was optimised for a shorter range, it ...

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by RJMAZ
Wed Aug 30, 2017 7:50 am
Forum: Civil Aviation
Topic: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus
Replies: 48
Views: 8748

Re: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus

7 abreast lightweight 767-400 makes no sense. No CASM advantage. 8 abreast lightweight 767-300 makes more sense. Slight CASM advantage maybe 5%. A clean sheet, light, narrow, shortish ranged, ld3-45 holding, tight 7 abreast makes complete sense. Big CASM advantage maybe over 10%. As the CASM improve...

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by RJMAZ
Wed Aug 30, 2017 5:22 am
Forum: Civil Aviation
Topic: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus
Replies: 48
Views: 8748

Re: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus

When comparing to the 767. The 787 has seats a full inch narrower while using the same width aisles. The A350 seats are half an inch narrower while using the same width aisles. A plane with 3-5-3 would want wider aisles than a 2-3-2 cabin. The 767 could easily have narrower aisles than the A350 and ...

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by RJMAZ
Wed Aug 30, 2017 2:20 am
Forum: Civil Aviation
Topic: Boeing 787 as starting point Large NMA / MoM, unlikely?
Replies: 110
Views: 17949

Re: Boeing 787 as starting point Large NMA / MoM, unlikely?

Instead of starting a new post. The 787-8 has nearly run out of orders to fill. I think it makes sense that a heavily lightened aircraft optimised for short range be developed. Now that Boeing has proven service experience with composites I think another 10T could be removed from the 787-3 design br...

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by RJMAZ
Tue Aug 29, 2017 11:10 pm
Forum: Civil Aviation
Topic: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus
Replies: 48
Views: 8748

Re: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus

Airlines prefer frequency but not at the expense of worse cost per seat mile. Airlines will only pick a smaller aircraft if its CASM is equal or better than the larger aircraft. The 777 and 787 manages to equal the CASM of the A380 due to better optimisation in the 777 and newer materials in the 787...

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by RJMAZ
Tue Aug 29, 2017 1:10 pm
Forum: Civil Aviation
Topic: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus
Replies: 48
Views: 8748

Re: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus

Use 787 flightdeck, maybe a new wing box and shorter 787 style wings, hang GEnx2Bs under those, new LGs (if needed) and presto :!: - we have our true 5,000nm 764MAX . :bigthumbsup: I guess development cost for that would be considerably less thus improving the business case and pricing flexibility....

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by RJMAZ
Tue Aug 29, 2017 12:15 pm
Forum: Civil Aviation
Topic: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus
Replies: 48
Views: 8748

Re: MoM Trans-Pacific Markets 2025-2040, Boeing & Airbus

A 5000nm MOM won't happen. Its CASM won't be low enough and will sell poorly. There are some rough trends that exist in the industry. Shrinks have higher CASM and stretches have lower CASM in the same family. To further explain why I'll give some examples. If you had three planes optimised to fly 60...

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by RJMAZ
Sun Aug 27, 2017 11:42 am
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

You really have that backwards, the market you propose is so crowded that they shouldn't be betting billions of dollars on an moonshot turboprop. You have current generation aircraft of 737-MAX7, A319NEO, E190/195v2, CRJ-1000, and plenty of second hand last generation 737-700s and A319 that could b...

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by RJMAZ
Sun Aug 27, 2017 3:35 am
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

The real problem is that the CS100 is a mainline-sized aircraft. Even though there is a 90-seat version of the Dash 8 available, in North America, scope clauses limit the Dash 8-Q400 to 76 passengers, and as such, the Dash 8 is a regional turboprop and rarely mainline. I don't see where a mainline ...

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by RJMAZ
Sun Aug 27, 2017 2:56 am
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

Look. You're bonkers/nutters/uninformed. The feeling is mutual. Landing loads DO get transfered through the wing box. Each MLG pretty much bolts to the ends of the wing box. The entire weight of the landing goes through the wingbox with the fuselage pushing down and the MLG pushing up. Regional air...

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by RJMAZ
Sat Aug 26, 2017 12:10 pm
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

Are you just making stuff up? Please provide some reason to think that regional airports cause more wear. Also, the other stuff you wrote (see post #12) was bonkers too. With shorter runways there is more pressure to land at the TDZ. In wet weather or with a tail wind it's often safer to slam down ...

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by RJMAZ
Sat Aug 26, 2017 12:45 am
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

Boeing and Airbus aren't interested in the 100 seat marked, 500nm stage length. Of course they are interested. Their shrinks are simply uncompetitive. They are overweight, have derated engines and have the capability to fly 3000+ miles. The average stage length of the worldwide 737 and A320 fleets ...

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by RJMAZ
Fri Aug 25, 2017 4:31 pm
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

I like this concept, although I don't see Bombardier develop this one. I think Bombardier should put their development efforts in the proposed CS500 before tackling this. The whole idea behind the CS500 is to get the CASM lower than the CS300. By trading range for extra seats with a simple stretch....

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by RJMAZ
Fri Aug 25, 2017 4:10 pm
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

I see no way on earth this much heavier concept could compete on operating costs vs even today's ATR This Q1000 proposal with 6 abreast would have twice as many seats as the ATR72. Of course it will be heavier and burn more fuel per trip, but it's the cost per passenger that is important. The CS100...

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by RJMAZ
Fri Aug 25, 2017 2:05 pm
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

That said there is still a lot of structure outside the wings that would be be complete overkill for the turboprop. The CS100 is already overbuilt for a 100 seater; the design, not just the wings, is not optimized for that segment. The life of an aircraft is determined by landing cycles. Landing an...

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by RJMAZ
Fri Aug 25, 2017 12:07 pm
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

I just flew two legs in Westjet Q400's...and I was very impressed. I had plenty of legroom, (I'm 6'1"), and I had 3 inches of knee room to the seat in front of me and could easily stretch right out. Both legs were about an hour long...and both flights were packed. To me, stretching the Q400 in...

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by RJMAZ
Fri Aug 25, 2017 9:41 am
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

You can not use the fuselage, as it designed for the heavy CS300. If you use it for a plane with less range and a lower MTOW it just becomes not efficient. The fuselage is designed to carry payload which is one of the main factors that determines how strong and heavy the tube must be. The payload w...

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by RJMAZ
Fri Aug 25, 2017 12:01 am
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

The CS100 is carrying too much dead weight outside of just its wings (to support higher MTOWs and larger variants) to make this viable. Actually the extra strength in the wing box and landing gear that you consider dead weight would be extremely useful in a turboprop variant. Higher approach angles...

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by RJMAZ
Thu Aug 24, 2017 12:41 pm
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Re: Bombardier Q1000

I disagree. The C series has the longest range and best economics in the 100-150 seat market. A short ranged prop version would compliment it. Embraers E-170 and E-190 aircraft with their shorter range would be hit the hardest. The added benefit would be the cost savings for the C series. With a lar...

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by RJMAZ
Thu Aug 24, 2017 11:46 am
Forum: Civil Aviation
Topic: Bombardier Q1000
Replies: 79
Views: 22958

Bombardier Q1000

http://members.iinet.net.au/~1300subbox/Q1000.jpg Bombardiers Q400 order sheet is getting low. Instead of a clean sheet replacement I would think a rewinged CS100 could be developed for trips under 1000nm. The CS100 and CS300 would still remain the obvious choice for medium haul. Using the fuselage...

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by RJMAZ
Wed Aug 23, 2017 7:14 am
Forum: Civil Aviation
Topic: ATR Going For All New 100 Seat Turboprop ?
Replies: 100
Views: 31937

Re: ATR Going For All New 100 Seat Turboprop ?

Pratt's next gen turboprop going all the way up to 8000hp? I assume there is a future military transport aircraft that will taking the 8000hp. A twin engine composite Hercules replacement maybe. That's enough power for Bombardier to built a turboprop the size of the CS100. How feasible would a strai...

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by RJMAZ
Wed Aug 09, 2017 4:17 am
Forum: Technical/Operations
Topic: Before/after retirement: What's your plane for you, and/or family?
Replies: 22
Views: 1717

Re: Before/after retirement: What's your plane for you, and/or family?

A good condition Piper PA-31 Navajo

Twin 6 cylinder Continentals engines. One of the faster piston engine aircraft. Great range and low fuel consumption. Enough room for the wife and kids definitely the most realistic and practical option.

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by RJMAZ
Sat Jun 17, 2017 10:30 pm
Forum: Civil Aviation
Topic: Boeing 797/MOM Discussion Thread
Replies: 585
Views: 86326

Re: 797/MOM Discussion Thread

With a potential smaller lower lobe for LD3-45s, are we looking at the resurrection of the double bubble fuselage? This is highly likely. You have 95% of the drag advantages of an oval but zero added structural weight. It will look slightly oval to the eye but it would be a double bubble. The 737 a...

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by RJMAZ
Fri Jun 16, 2017 3:18 am
Forum: Civil Aviation
Topic: Boeing 797/MOM Discussion Thread
Replies: 585
Views: 86326

Re: 797/MOM Discussion Thread

Indeed. It could very well be argued that the market is too small to justify an all new aircraft for such a narrow operational requirement. That's why I think an A322 would fare better. Problem for Boeing is that doing a comparable 737 MAX-11 would require too many changes to make it worthwhile. Ad...

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by RJMAZ
Fri Jun 16, 2017 2:56 am
Forum: Civil Aviation
Topic: Boeing 797/MOM Discussion Thread
Replies: 585
Views: 86326

Re: Another 797/MOM Article

Don't know if you are serious about a 230 passenger 5000 nm A321...but if you are...that's really not an option, It would mean a new wing, new engines, and unless 230 passengers want to sit 10 hours with their knees up to the chin -- a longer fuselage, new gear and empennage...Not just $2 billion, ...

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by RJMAZ
Thu Jun 15, 2017 3:58 am
Forum: Civil Aviation
Topic: Boeing 797/MOM Discussion Thread
Replies: 585
Views: 86326

Re: 797/MOM Discussion Thread

LD3-45 would be a perfect fit for a 170" high 192" wide fuselage. It definitely wouldn't be able to fit anything taller, but maybe something slightly wider.

It definitely wouldn't fit LD3's as even the 767 had to use smaller LD2's.

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by RJMAZ
Wed Jun 14, 2017 6:11 am
Forum: Civil Aviation
Topic: Boeing 797/MOM Discussion Thread
Replies: 585
Views: 86326

Re: 797/MOM Discussion Thread

Some weight estimates for the MOM. A 767-300 is 14% longer than the 767-200 yet its empty weight is 7% more. The percentage weight increase was approximately half of the percentage length. I would roughly assume the fuselage accounts for approximately 50% of the aircraft weight. So with the 767-200 ...

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by RJMAZ
Tue Jun 13, 2017 7:35 am
Forum: Civil Aviation
Topic: Boeing 797/MOM Discussion Thread
Replies: 585
Views: 86326

Re: 797/MOM Discussion Thread

You don't need to have an oval fuselage to make the aircraft wider than it is high. The double bubble concept for years has allowed for an aircraft to have a taller fuselage than its width. The same concept can be used to make the fuselage wider. Above floor level the fuselage can be a perfect circl...

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by RJMAZ
Mon Mar 06, 2017 3:19 am
Forum: Civil Aviation
Topic: Next aircraft program at Bombardier
Replies: 156
Views: 26263

Re: Next aircraft program at Bombardier

Belly tanks for the CS100 and its maximum takeoff weight increased to the same as the CS300. This creates the CS100LR. What could the range be? It depends on the payload and flight direction. But in a comfortable 2 class configuration it would equal or slightly exceed any 737 or a320 version. These...

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by RJMAZ
Thu Mar 02, 2017 3:09 am
Forum: Civil Aviation
Topic: Next aircraft program at Bombardier
Replies: 156
Views: 26263

Re: Next aircraft program at Bombardier

Belly tanks for the CS100 and its maximum takeoff weight increased to the same as the CS300. This creates the CS100LR. Allowing flights from western Europe to cover most of the US. CS500 will happen as the wing is so bloody big it can handle the stretch. I'm betting on a Q400 being converted into a ...

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by RJMAZ
Wed Mar 01, 2017 2:12 am
Forum: Technical/Operations
Topic: Future of aircraft design
Replies: 33
Views: 9641

Re: Future of aircraft design

I'm betting on electric propulsion for most regional flights. Sort of like a BMW i3 they would have an optional range extender which can be used on longer distance regional flights. Electric driven props or fans would allow for extreme STOL performance and quiet operation from small airports. This w...

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by RJMAZ
Fri Aug 12, 2016 11:56 am
Forum: Civil Aviation
Topic: Leeham reports on 787 production rate discussion
Replies: 129
Views: 16031

Re: Leeham reports on 787 production rate discussion

There's no demand to produce 168 787s per year. At this rate the backlog would be depleted soon, forcing Boeing to reduce the production rate. No you are wrong. Boeing wont increase production if they just have to reduce it again a few years later. There is a term called the death spiral in militar...

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by RJMAZ
Fri Aug 12, 2016 4:57 am
Forum: Civil Aviation
Topic: Leeham reports on 787 production rate discussion
Replies: 129
Views: 16031

Re: Leeham reports on 787 production rate discussion

There are factors people aren't considering. Going from 12 per month to 14 will allow each aircraft to be built cheaper. A 5% reduction in production cost per aircraft is possible and would be a very big deal. If that cost saving is passed onto the customer Boeing will easily sell the two extra airc...

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by RJMAZ
Tue Jul 19, 2016 11:56 pm
Forum: Civil Aviation
Topic: Leahy: MOM Market Already Taken By A321neo
Replies: 189
Views: 24671

Re: Leahy: MOM Market Already Taken By A321neo

That is what the 787-3 was for and it failed dismally. That is bang in this supposed MoM. Again the 787-3 was a shrink of the family. Shrinks are usually designed for extra range or takeoff performance. The 787-3 had its wings cropped and werent optimised. It was also carrying heaps of empty space ...

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by RJMAZ
Tue Jul 19, 2016 10:49 am
Forum: Civil Aviation
Topic: Leahy: MOM Market Already Taken By A321neo
Replies: 189
Views: 24671

Re: Leahy: MOM Market Already Taken By A321neo

I am sitting here and wonder if the whole industry forgot history. The 767-300 did not sell well, the ER did. The 200 sold poorly overall. The shrink of the family never sells well. The shrink is usually designed to provide a little extra range or better take off performance on short runways. CASM ...

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by RJMAZ
Tue Jul 19, 2016 4:54 am
Forum: Civil Aviation
Topic: Leahy: MOM Market Already Taken By A321neo
Replies: 189
Views: 24671

Re: Leahy: MOM Market Already Taken By A321neo

Its all about moving more air at a slower speed. Force = mass X velocity^2 So less velocity means less force, no? Incorrect. Lots of people get this wrong. Velocity is squared. I'll try to explain it with some made up numbers. You could have 20,000lb of thrust from a 100inch fan moving at 2000rpm. ...

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by RJMAZ
Tue Jul 19, 2016 12:58 am
Forum: Civil Aviation
Topic: Leahy: MOM Market Already Taken By A321neo
Replies: 189
Views: 24671

Re: Leahy: MOM Market Already Taken By A321neo

There is no way in the world you are going to get 15% better SFC and no way in the world there is 20-25% fuel efficiency improvement for a smaller plane by 2025. To get better than the 789, you need to go bigger (78X), not smaller. If you believe these numbers the maybe Airbus should start selling ...

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by RJMAZ
Tue Jul 19, 2016 12:29 am
Forum: Civil Aviation
Topic: Leahy: MOM Market Already Taken By A321neo
Replies: 189
Views: 24671

Re: Leahy: MOM Market Already Taken By A321neo

For a given capacity, a longer single aisle fuselage is significantly lighter than a short wide one. Comparing the 757-300 to the 767-200 is interesting in that respect. At some point a wide fuselage becomes more structurally efficient. But not below 45 rows economy class. You are just assuming thi...

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by RJMAZ
Mon Jul 18, 2016 11:19 am
Forum: Civil Aviation
Topic: Leahy: MOM Market Already Taken By A321neo
Replies: 189
Views: 24671

Re: Leahy: MOM Market Already Taken By A321neo

Interesting - a rewinged 767. There are a couple differences between our suggestions - my model assumes a new oval fuselage that has 10% less wetted area and 10% less weight (I assume that Boeing gives back the weight savings per m2 because of strengthening for non-circular cross section. The oval ...

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by RJMAZ
Mon Jul 18, 2016 11:12 am
Forum: Civil Aviation
Topic: Leahy: MOM Market Already Taken By A321neo
Replies: 189
Views: 24671

Re: Leahy: MOM Market Already Taken By A321neo

14% lighter than a 767-300 is still over 50% heavier than a A321. And the wider fuselage will have a drag penalty. Imho no design depending on an engine advantage is viable in todays market space. If you can not make it work using engines of the same technology level on your plane and the competiti...

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by RJMAZ
Mon Jul 18, 2016 4:36 am
Forum: Civil Aviation
Topic: Leahy: MOM Market Already Taken By A321neo
Replies: 189
Views: 24671

Re: Leahy: MOM Market Already Taken By A321neo

By my quick estimations, it's possible to have 5,000nm range with a 284,000lb MTOW, 40k thrust engines, 2,300ft2 wing, 156ft span (same as 763). OEW decreases from 187,900lbs to ~162,000lbs. That's ~14% lighter, which seems conservative given CFRP and a much more modern design that needs to lift mu...

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by RJMAZ
Sat Jul 16, 2016 2:29 am
Forum: Civil Aviation
Topic: Leahy: MOM Market Already Taken By A321neo
Replies: 189
Views: 24671

Re: Leahy: MOM Market Already Taken By A321neo

I am sure this has been discussed before in the hundreds of Boeing MOM and NSA threads, but what is the major reason why the two projects can't be combined? . The Max 8 is actually outselling the A320neo if you take into account that the max 8 was launched later. The Max 8 burns less fuel than the ...

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by RJMAZ
Fri Jul 15, 2016 5:59 am
Forum: Technical/Operations
Topic: My math must be off. A 150 seat A380 LHR-JFK can't be ~$500pp
Replies: 54
Views: 8355

Re: My math must be off. A 150 seat A380 LHR-JFK can't be ~$500pp

You can't run a fleet of 1. Any mechanical problem or delays would destroy the reputation of the company. A large fleet allows aircraft to be repositioned to cover any delays in the network. Premium customers will not accept delays so you need a spare aircraft to cover that 1 in 100 mechanical fault...

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