Blackbird
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Lockheed Tristar / RB-211-22

Sat Jun 09, 2007 11:39 am

Why did Lockheed whole-heartedly go for the RB-211 and not at least keep a back-up like the GE CF-6 just in case the design didn't develop right?

Andrea K
 
KELPkid
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RE: Lockheed Tristar / RB-211-22

Sat Jun 09, 2007 11:47 am

IIRC, some significant British orders were depending on the engine selection...
Celebrating the birth of KELPkidJR on August 5, 2009 :-)
 
Viscount724
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RE: Lockheed Tristar / RB-211-22

Sat Jun 09, 2007 12:07 pm

This is a good summary of the very messy L1011 and RB-211 history that came close to putting both Lockheed and Rolls-Royce out of business.
http://www.globalsecurity.org/milita...ystems/aircraft/l-1011-history.htm
 
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RE: Lockheed Tristar / RB-211-22

Sat Jun 09, 2007 9:35 pm

Quoting Viscount724 (Reply 2):
This is a good summary of the very messy L1011 and RB-211 history that came close to putting both Lockheed and Rolls-Royce out of business.

Thanks for posting this; it provided some very interesting history that I was unaware of. One thing I did not realize was that the L-1011 HAD to have the RB-211 because neither of the other available engines would fit in the tail because of length.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 3:59 am

Actually I remember hearing that they were considering using a CF-6 Variant as a back-up but for some reason they never decided to use the back-up,

In regards to KELPKid's statement... even if they had the CF-6 as an option with the RB-211 as the primary option, wouldn't they have had the same opportunity in the British market?
 
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 4:28 am

The RB.211 engine was chosen primarily for noise and fuel efficiency considerations.

Lets review.

ALL models of the L1011 ware stage three noise compliant at ALL weights.
This cannot be said of some of the DC-10 and B747 models.

In addition, the RB.211 was (approximately) 11% more fuel efficient than the CF6 engines THEN currently available.
 
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Jetlagged
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 4:58 am

These days we are used to multiple engine variants on airliners. When the L-1011 was designed it was almost unheard of. I don't remember RB211 exclusivity on the TriStar seeming particularly unusual at the time. P&W were on the 747 and GE were on the DC-10. The A300 was one of the first jet airliners to have engine options designed in, with P&W and GE offering compatible engines.

Also, the centre engine of a tri-jet is the hardest mount to make alternate engines fit. The S duct inlet would have been especially hard to match for two very different engine types.

If the carbon fibre fan had worked it would have been a huge advantage for the RB211. The JT9D and CF6 would have been outclassed. So the RB211 must have looked a good bet. When the RB211 ran into trouble, Lockheed had no alternative but to stick with it or sink with it.

As for sales in the UK market, this would have been secondary for Lockheed. Their prime market was US domestic. it is true that BA at the time normally bought British engines, but that didn't stop them buying the 747-100 with P&W engines.
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BA777
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 5:57 am

A little off-topic but does anyone have an actual recording of this RB-211-22 startup from outside?
 
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 7:13 am

Why was the carbon fiber they designed too weak? Was there anything they could have done to have made them stronger with the technology they had at the time?

Why did United choose the DC-10 over the L-1011? Was it because the engine wasn't ready on time? Or did they really want the CF-6?

If Lockheed signed a deal with the RB-211, but kept the CF-6 engine on as a "just in case" situation, would it have been a major financial issue? Because I remember reading about them considering a CF-6 variant...

Andrea Kent
 
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 9:00 am

Quoting Jetlagged (Reply 6):
The A300 was one of the first jet airliners to have engine options designed in, with P&W and GE offering compatible engines.

Of the approximate 250 early model A300B2/B4s (those prior to the updated -600), only about 25 had P&W engines. I believe the only early A300 customers that ordered P&W engines were SAS, Iberia, China Airlines and Garuda, probably for increased commonality with engines on their early 747s.
 
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 9:09 am

Quoting BA777 (Reply 7):
A little off-topic but does anyone have an actual recording of this RB-211-22 startup from outside?

No, but I do have two links to the RB-211-22 spooling up. Though I think what you really wanted to see was all the smoke coming from those engines. They were notorious for smoking upon start.

Anyway, enjoy.....

http://www.flightlevel350.com/Aircra...Air_Lines_Aviation_Video-6141.html

http://www.flightlevel350.com/Aircra...Air_Lines_Aviation_Video-1742.html


BTW, I have a technical question. I had a book about Airliners, and I still think it's in my old room at my parents, but it stated that the Lockheed L-1011 had an advantage of being able to put the wing engines further out on the wing, thus reducing wing flex and wear and tear on the wings, because the #2 engine was placed directly behind the aircraft, as opposed to the DC-10 #2 engine which was above the aircraft. If you look at the DC-10 engines vs. the L-1011 engines, the DC-10's #1 and #3 engines are much closer to the fuselage than the Tristar. Why does the position of the #2 engine determine how far out you could put the #1 and #3 engines?


UAL
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Jetlagged
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 9:59 am

Quoting Blackbird (Reply 8):
Was there anything they could have done to have made them stronger with the technology they had at the time?

Probably not. GE finally managed to succeed with composite fan blades on the GE90, over twenty years later, due to improved materials and advanced software modelling.

Quoting Viscount724 (Reply 9):
Of the approximate 250 early model A300B2/B4s (those prior to the updated -600), only about 25 had P&W engines. I believe the only early A300 customers that ordered P&W engines were SAS, Iberia, China Airlines and Garuda, probably for increased commonality with engines on their early 747s

It wasn't a popular option, that's for sure.
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474218
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 10:38 am

Quoting Jetlagged (Reply 6):
As for sales in the UK market, this would have been secondary for Lockheed. Their prime market was US domestic. it is true that BA at the time normally bought British engines, but that didn't stop them buying the 747-100 with P&W engines.

There were three launch customers for the L-1011, Eastern, TWA and Air Holdings. Air Holdings was a UK company that was up to off set the use of British engines. Air Holdings ordered 30 L-1011's (with 20 options) for sale outside the United States.

Quoting UAL747 (Reply 10):
Why does the position of the #2 engine determine how far out you could put the #1 and #3 engines?

The position of the L-1011's No.2 engine (closer to the center line of the fuselage) allowed for a larger rudder. The larger rudder allowed the L-1011's wing engines to be seven (7) feet further outboard than the DC-10.'s.

Quoting 411A (Reply 5):
ALL models of the L1011 ware stage three noise compliant at ALL weights.

Not quite true, ANA did not pay to have the Stage 3 requirements in their flight manuals. Therefore, their L-1011's were only certified to Stage 2. When they were sold, the buyer had to come to Lockheed to have the AFM's revised. For a nominal charge (big $) as it was a paper work change only.

Quoting Blackbird (Reply 8):
Why did United choose the DC-10 over the L-1011?

United never flew Lockheed's.
 
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 10:51 am

Quoting 474218 (Reply 12):
The position of the L-1011's No.2 engine (closer to the center line of the fuselage) allowed for a larger rudder. The larger rudder allowed the L-1011's wing engines to be seven (7) feet further outboard than the DC-10.'s.

Ah, okay, I see. So if the DC-10 had engines as far out as the L-1011, but with the smaller rudder, the rudder couldn't compensate enough for the engine out on the right or left side.

That right?

UAL
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 11:07 am

Quoting UAL747 (Reply 13):
Ah, okay, I see. So if the DC-10 had engines as far out as the L-1011, but with the smaller rudder, the rudder couldn't compensate enough for the engine out on the right or left side.

That right?

That is correct!
 
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 11:47 am

Quoting 474218 (Reply 12):
Quoting Blackbird (Reply 8):
Why did United choose the DC-10 over the L-1011?

United never flew Lockheed's.

Yes they did, but not for long. They inherited 6 ex-Pan Am L1011-500s (and 11 B747SPs) as part of their purchase of PA's Pacific routes in 1985. UA only kept the L1011s for about 2 years. UA sold them to DL.


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[Edited 2007-06-10 04:49:15]
 
474218
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 12:30 pm

I should have said United never "bought" Lockheed aircraft. Actually United liked the L-1011-500, it was an excellent fit for there far east routes. But with so few in the fleet and no way to obtain more they passed them on to Delta, who could not get their had on enough.
 
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RE: Lockheed Tristar / RB-211-22

Sun Jun 10, 2007 1:01 pm

Speaking of Delta, I had a long discussion with one of their senior VP's after the last of their L1011's were parked, and his exact comments were...

The L1011 made Delta the most profit of any airplane in our fleet, bar none.

Surprised?
I'm not.
 
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RE: Lockheed Tristar / RB-211-22

Mon Jun 11, 2007 12:51 am

Quoting 411A (Reply 17):
The L1011 made Delta the most profit of any airplane in our fleet, bar none.

In the mid 1980's Lockheed held a Operators/Suppliers conference, to insure the L-1011 continued to have spares. At that conference a Delta VP said, 'we operate a fleet of fifty L-1011's and each one of them generates $80,000 in revenue a day, and that is why we get upset when an aircraft is AOG for spares.
 
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RE: Lockheed Tristar / RB-211-22

Mon Jun 11, 2007 3:09 am

Quoting 411A (Reply 17):

The L1011 made Delta the most profit of any airplane in our fleet, bar none.

Why did they park them? They still had plenty of life left, didn't they?
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
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RE: Lockheed Tristar / RB-211-22

Mon Jun 11, 2007 4:22 am

Quoting 474218 (Reply 18):
In the mid 1980's Lockheed held a Operators/Suppliers conference, to insure the L-1011 continued to have spares



Quoting SEPilot (Reply 19):
Why did they park them? They still had plenty of life left, didn't they?

One of the reasons we retired them from '98-'01 was because by that time spare part availability was becoming an issue. I once worked a flap track fitting replacement on one of our L-1011-250s. Lockheed didn't have a new one and the lead time was 120 days IIRC. We robbed one off of a parked bird in VCV but the holes in that fitting didn't line up with the ones in our aircraft. Lockheed ended up finding one but I'm pretty sure they didn't have any more as they weren't supposed to even have the one they sold us for $60,000.

The whole picture of why we retired the L-10 wasn't just about spares. The birds were becoming maintenance pigs. They weren't nearly as fuel efficient as the 764 that was supposed to replace them while eliminating the SO and thereby thinning the pilot ranks. It served DL well and DL did more than any other airline in keeping them flying and finding useful solutions to make the plane as successful as it was. It's time had come. Had we known about the coming financial disaster for the company maybe they would have stayed around a little longer. But as they say say hindsight is 20/20.

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RE: Lockheed Tristar / RB-211-22

Mon Jun 11, 2007 6:42 am

Quoting Jetlagged (Reply 6):
it is true that BA at the time normally bought British engines, but that didn't stop them buying the 747-100 with P&W engines.

They had no choice on the 747-100 as there were no engine options then. The only 747-100s without P&W engines were 8 -100B models (with certain -200 features) for Saudi Arabian Airlines. They had R-R RB211s but weren't built until 1981/82, 5 or 6 years after the last standard 747-100s had been delivered.

Apart from BA's early 707-420s with R-R Conways, they also bought later, more capable, P&W-powered 707-320Cs (and 737-200s). In earlier years, their Constellations, Stratocruisers and DC-7Cs of course had US engines, but at the time there were no comparable British-built aircraft that could do the same job.
 
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RE: Lockheed Tristar / RB-211-22

Mon Jun 11, 2007 9:04 am

What aspects about the L-1011 made it the biggest revenue maker for Delta Airlines?

Andrea K
 
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RE: Lockheed Tristar / RB-211-22

Mon Jun 11, 2007 11:14 am

Mature design, large capacity, all-weather capability, quiet.
And, last but not least, believe it or not, customer preference/satisfaction.

You might be surprised at the comments I receive when folks find out I still fly the TriStar, such as....gosh, I sure miss those big spacious cabins, or....most comfortable plane I have flown in, sad they're gone.

Speaking of quiet, if you go to the small village of Morfeldon, just south of the FRA airport, you will find, at the end of one street, a recording noise meter.

The important stuff is on the inside of the big steel box, but visible on the outside, is a DB meter.
It is, believe it or not, a gathering place in the evening for some local residents.
When I was there a few years ago, many of these folks lamentated the withdrawal of TriStar services to FRA, as they insisted it was the quietest large jet of 'em all.

I suspect they're right.
 
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RE: Lockheed Tristar / RB-211-22

Mon Jun 11, 2007 9:19 pm

Quoting Viscount724 (Reply 21):
They had no choice on the 747-100 as there were no engine options then.

That was exactly my point. I thought the implication was obvious....

However when they bought 747-200s they chose RB211 power, rather than sticking with JT9Ds for commonality.
The glass isn't half empty, or half full, it's twice as big as it needs to be.
 
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RE: Lockheed Tristar / RB-211-22

Mon Jun 11, 2007 10:26 pm

Quoting Blackbird (Reply 8):
Why was the carbon fiber they designed too weak? Was there anything they could have done to have made them stronger with the technology they had at the time?

The carbon fibre was strong enough to perform the day job. Just got all uppity when it hit hail or birds. Look at a GE90 fan blade, and note the big steel strip on the leading edge. That's why it is there. I overheard a GE guy at Farnborough saying that the blade is in reality no lighter than an RR titanium blade, but it is a product differentiator. And apparently GE had a really hard time containing the steel strip on blade containment testing.
 
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RE: Lockheed Tristar / RB-211-22

Tue Jun 12, 2007 2:02 am

I remember hearing that United would have bought the L-1011 if they would have used a CF-6 variant, and Lockheed decided not to and United bought the DC-10 (there may have been other reasons involved though)

I think I remember hearing something about Lockheed considering the CF-6 as a backup, but decided against it for one reason or another. Anybody know why?

Andrea K
 
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RE: Lockheed Tristar / RB-211-22

Tue Jun 12, 2007 2:52 am

Quoting Blackbird (Reply 22):
What aspects about the L-1011 made it the biggest revenue maker for Delta Airlines?

411A is a truly unapologetic L-1011 enthusiast and knows a lot about the aircraft. He does make good points. The L-1011 was definitely ahead of its time technologically. Sadly, having the better product does not necessarily equate to winning in the marketplace.

Why? There are many reasons, including time to market and "political issues" like preferred suppliers. Also, hindsight is 20/20. At the time of initial entry into service, all the operators can really do is make educated guesses about service life. There is no way to be absolutely certain about costs and maintenance issues. For example, could the operators predict the MD-11 burning so much more fuel than expected? Not when they placed the initial orders years before the aircraft flew.

Quoting Blackbird (Reply 26):
I remember hearing that United would have bought the L-1011 if they would have used a CF-6 variant, and Lockheed decided not to and United bought the DC-10 (there may have been other reasons involved though)

Probably as you say there are other reasons. I guess if Lockheed had had prospects for, say, 150 extra frames "as long as they have the CF-6" then it would have happened.
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RE: Lockheed Tristar / RB-211-22

Tue Jun 12, 2007 6:58 am

The biggest reason for the L1011 failing is the decision to build it. After Douglas had announced the DC-10 first, it was ego more than sound decision making. Both companies knew the market wouldn't support two airframes that size profitably, but they played chicken anyway and since neither one blinked, both lost their footholds in the commercial aviation world. Lockheed never produced another plane, and McD hung around refreshing their old designs for another 20 years before Boeing gobbled them up.

If Lockheed wanted to play, they could/should have found another market segment waiting for a new airframe. A 767/A300/757 style airplane was within reach and showed that there was a market just a little later down the road...
There are 10 kinds of people in the world; those who understand binary, and those that don't.
 
474218
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RE: Lockheed Tristar / RB-211-22

Tue Jun 12, 2007 8:13 am

Quoting Lemurs (Reply 28):
The biggest reason for the L1011 failing is the decision to build it. After Douglas had announced the DC-10 first, it was ego more than sound decision making.

There is a real problem with this statement, Lockheed actually launched the L-1011 over a year before Douglas made the decision to build the DC-10.
 
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RE: Lockheed Tristar / RB-211-22

Tue Jun 12, 2007 9:54 am

Still, I'm suprized they didn't keep the CF-6 as a back-up... the RB-211-22 was a revolutionary engine with, at the time, new technology.

Andrea K
 
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RE: Lockheed Tristar / RB-211-22

Tue Jun 12, 2007 9:58 am

Quoting Jetlagged (Reply 24):
However when they bought 747-200s they chose RB211 power, rather than sticking with JT9Ds for commonality.

However, by then BA also had a sizable L1011 fleet so the RB211 had commonality benefits there. And BA was still goverrnment-owned then which no doubt had some influence on the decision to support R-R, especially after the government had been forced to nationalize Rolls-Royce after they became insolvent and went into receivership in 1971 due to RB211 development problems and huge cost overruns.

BA of course later became one of the few carriers to order 767s with R-R engines, and of course their 757s and 744s.

Having your major engine supplier located cose to your maintenance facilities probably also had some benefits when parts were needed urgently.
 
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RE: Lockheed Tristar / RB-211-22

Tue Jun 12, 2007 11:27 am

Quoting Blackbird (Reply 30):
Still, I'm suprized they didn't keep the CF-6 as a back-up... the RB-211-22 was a revolutionary engine with, at the time, new technology.

Airbus bet on the SuperFan for the 340 too. Oops.
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RE: Lockheed Tristar / RB-211-22

Tue Jun 12, 2007 11:33 am

Still, how hard would it have been to have kept the CF-6 as a back-up just in case?

Andrea K
 
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RE: Lockheed Tristar / RB-211-22

Tue Jun 12, 2007 12:30 pm

Quoting Blackbird (Reply 33):
Still, how hard would it have been to have kept the CF-6 as a back-up just in case?

Very. Given the #2 engine position it's not just a question of redesigning the pylon. Apart from the pylon, the tail might have needed a redesign. But more significantly, the S-duct is really expensive to design even once. Very sophisticated aerodynamics. The 727 had surge problems on #2 throughout it's service life, including one on rotation during the very first flight.
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RE: Lockheed Tristar / RB-211-22

Wed Jun 13, 2007 3:17 am

Quoting 474218 (Reply 29):
There is a real problem with this statement, Lockheed actually launched the L-1011 over a year before Douglas made the decision to build the DC-10.

Ahh, I got the order reversed. Oops. Regardless, they both had their fingers on their own ABORT buttons, but neither actually pushed it. You can argue about whose particular fault it was by jumping into the fray second, but the fact is that both had everything to lose by going forward with essentially identical plans, and they did in fact both lose everything. McD just pushed it off further because they had the DC-9/MD-80 to fall back on for a few years.
There are 10 kinds of people in the world; those who understand binary, and those that don't.
 
474218
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RE: Lockheed Tristar / RB-211-22

Wed Jun 13, 2007 4:18 am

Quoting Lemurs (Reply 35):
Ahh, I got the order reversed.

Try to find a copy of the book "The Sporty Game" by John Newhouse. Provides an overview of the DC-10, L-1011 and 747 and how they were designed, built and sold (selling be the sporty game). In the book there is a section on how the airlines tried to get McD to drop the three engine DC-10 an go with a twin, because Lockheed was ahead of them with their three engine design.
 
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RE: Lockheed Tristar / RB-211-22

Wed Jun 13, 2007 7:08 am

Starlionblue,

I'm pretty sure that statement in that link about them needing an unusually short engine for the number 2 pylon was simply a myth. I've never heard any data to suggest such a thing. Regarding the S-duct... both engines -- the CF-6 and RB-211 had the same diameter, 84/85-inches. They're about the same.


474218,

Why did McDonnell Douglas not abort their design if they were a full year behind on the DC-10?

Also, if they didn't go for the DC-10, what should they have developed in lieu of that?

Andrea K

[Edited 2007-06-13 00:11:10]
 
474218
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RE: Lockheed Tristar / RB-211-22

Wed Jun 13, 2007 8:10 am

Quoting Blackbird (Reply 37):
Why did McDonnell Douglas not abort their design if they were a full year behind on the DC-10?

See Reply 36!
 
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Jetlagged
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RE: Lockheed Tristar / RB-211-22

Wed Jun 13, 2007 8:30 am

Quoting Blackbird (Reply 37):
Regarding the S-duct... both engines -- the CF-6 and RB-211 had the same diameter, 84/85-inches. They're about the same.

Likely to be different inlet requirements though (mass flow, velocity, fan rpm). Matching the inlet to the engine is one of the hardest parts of engine installation design. There would be no guarantee that an S-duct designed to work for an RB211 would work for a CF6. It would only have to work slightly less well for it to be a big problem.

It also mentions aerodynamics and weight distribution issues and an estimated $100 million extra development cost and one year extra development time.

The fact that Lockheed chose not to switch to the CF6 tells you how uneconomic that would have been. If it was an easy answer, I'm sure Lockheed would have dropped the RB211 like a shot.

[Edited 2007-06-13 01:38:43]
The glass isn't half empty, or half full, it's twice as big as it needs to be.
 
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RE: Lockheed Tristar / RB-211-22

Wed Jun 13, 2007 8:44 am

Quoting Xv408 (Reply 25):
Look at a GE90 fan blade, and note the big steel strip on the leading edge. That's why it is there. I overheard a GE guy at Farnborough saying that the blade is in reality no lighter than an RR titanium blade, but it is a product differentiator. And apparently GE had a really hard time containing the steel strip on blade containment testing.

The leading edge is titanium, not steel. It's there more for hard body FOD (stones, etc) than birds and hail. GE does maintain that the fan system design with composite blades and matching disk is a lighter system. There were no difficulties containing the leading edge strip in containment tests. In total the GE90 fan blade is extremely durable and the scrap rate is vanishingly low (<20 blades in the history of the program).
My views are not necessarily the views of the GE Company
 
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RE: Lockheed Tristar / RB-211-22

Wed Jun 13, 2007 11:01 am

Quoting Blackbird (Reply 37):

I'm pretty sure that statement in that link about them needing an unusually short engine for the number 2 pylon was simply a myth. I've never heard any data to suggest such a thing. Regarding the S-duct... both engines -- the CF-6 and RB-211 had the same diameter, 84/85-inches. They're about the same.

Fine. But as Jetlagged mentions, different engines would still require quite different S-ducts. Given how hard and expensive those were in the first place...
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Blackbird
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RE: Lockheed Tristar / RB-211-22

Wed Jun 13, 2007 12:19 pm

Jetlagged Wrote:

Quote:
Likely to be different inlet requirements though (mass flow, velocity, fan rpm). Matching the inlet to the engine is one of the hardest parts of engine installation design. There would be no guarantee that an S-duct designed to work for an RB211 would work for a CF6. It would only have to work slightly less well for it to be a big problem.

Okay, what's the mass-flow, and engine-rpm for the RB-211-22 and the early CF-6 then? It is my opinion that it wouldn't take anything more than a slight-recontouring in some areas


Jetlagged Wrote:

Quote:
It also mentions aerodynamics and weight distribution issues and an estimated $100 million extra development cost and one year extra development time.

Where does it mention that using a CF-6 as a back-up would require 100-million extra dollars in development cost and an extra year of development?


Jetlagged Wrote:

Quote:
The fact that Lockheed chose not to switch to the CF6 tells you how uneconomic that would have been. If it was an easy answer, I'm sure Lockheed would have dropped the RB211 like a shot.

No, I didn't suggest they totally have switched to the CF-6... I mean they should have simply kept it as a back-up.


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RE: Lockheed Tristar / RB-211-22

Wed Jun 13, 2007 5:30 pm

Quoting Jetlagged (Reply 39):
Likely to be different inlet requirements though (mass flow, velocity, fan rpm). Matching the inlet to the engine is one of the hardest parts of engine installation design. There would be no guarantee that an S-duct designed to work for an RB211 would work for a CF6. It would only have to work slightly less well for it to be a big problem.

The original RB211-22 had 42000lbs, the later -524 had around 50000lbs using the same S duct. This is a lot more mass flow and it worked OK.
The problem was that you could not select take off thrust on a -524 at standstill, you needed some fwd speed to push the air into the duct.
When we did engine runs on the Nbr 2 engine -524 L1011, we never went to take off power! There was a set of charts in the MM to work out the max thrust you could select on the ground. With a crosswind you always had to be very careful or the engine started rumbling away.
 
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Jetlagged
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RE: Lockheed Tristar / RB-211-22

Thu Jun 14, 2007 12:00 am

Quoting Blackbird (Reply 42):
No, I didn't suggest they totally have switched to the CF-6... I mean they should have simply kept it as a back-up.

What would be the point of a backup plan if it was uneconomic or unfeasible to implement?
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RE: Lockheed Tristar / RB-211-22

Thu Jun 14, 2007 10:15 am

Quoting UAL747 (Reply 10):
No, but I do have two links to the RB-211-22 spooling up. Though I think what you really wanted to see was all the smoke coming from those engines. They were notorious for smoking upon start.

Anyway, enjoy.....

http://www.flightlevel350.com/Aircra...Air_Lines_Aviation_Video-6141.html

http://www.flightlevel350.com/Aircra...Air_Lines_Aviation_Video-1742.html

Thanks for the links! I only flew on 2 DL L1011's . I flew CVG-ZRH-CVG in July '95.I remember being bummed that we weren't on an MD-11.
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RE: Lockheed Tristar / RB-211-22

Fri Jun 15, 2007 5:09 pm

Quoting 411A (Reply 5):
ALL models of the L1011 ware stage three noise compliant at ALL weights.
This cannot be said of some of the DC-10 and B747 models.

I know some of the early B747 classic was louder than stage three, but I thought all model of DC10 was in stage three noise compliant.
 
mandala499
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RE: Lockheed Tristar / RB-211-22

Fri Jun 15, 2007 11:35 pm

Quoting 474218 (Reply 12):

Quoting 411A (Reply 5):
ALL models of the L1011 ware stage three noise compliant at ALL weights.

Not quite true, ANA did not pay to have the Stage 3 requirements in their flight manuals. Therefore, their L-1011's were only certified to Stage 2. When they were sold, the buyer had to come to Lockheed to have the AFM's revised. For a nominal charge (big $) as it was a paper work change only.

What's not true? All models of the L1011 were stage 3 noise COMPLIANT at all weights and as you said, not all certified them to Stage 3 noice compliance...

I'm just being picky...

And I miss them ten-elevens!!!!

Mandala499
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Blackbird
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RE: Lockheed Tristar / RB-211-22

Tue Jun 19, 2007 10:40 am

I think the L-1011 was an excellent aircraft and was great the way it was. It had a nice wide-fuselage, good passenger capacity, good-looks, capable of short takeoff runs, able to fly at decently high mach numbers (0.85-0.86 = M), highly reliable hydraulics with all sorts of safety features, state of the art auto-pilot which even had the 767-200 beat in some respects from what I was told, excellent pitch-control (able to takeoff even with full nose-down trim!) and good handling.

I'm simply stating that a lot of their early development troubles would have been more easily coped with had, say, the CF-6 been an option. In fact, UAL might have bought the L-1011 instead of the DC-10.

But seriously, how much would it have cost to use a CF-6 as an option? Was it really a hundred million bucks to have the L-1011 as an option and a slight adjustment to the tail?


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RE: Lockheed Tristar / RB-211-22

Tue Jun 19, 2007 10:59 am

Quoting Blackbird (Reply 48):
But seriously, how much would it have cost to use a CF-6 as an option? Was it really a hundred million bucks to have the L-1011 as an option and a slight adjustment to the tail?

100m sounds reasonable, not that I am an expert. Everything I have read about DC-10s, TriStars and 727s indicates the center inlet/engine mount is a very complex thing and expensive to develop.

It's also important to remember that hindsight is 20/20. Sure, the CF-6 looks like a no brainer today. Not so at the time probably.
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