Stretching airliners

[c52]

I was more than surprised to note the prototype BAe 146 G-LUXE flying the other day.

When it had finished being the prototype 146-100, it was sliced up, had bits inserted and was fastened back together again to make the prototype 146-300.

I can only think of the 1-11 that had previously been literally stretched - were there others?

[kenparry]

Not exactly an airliner; but all the stretched RAF C-130K examples (Hercules C3?) were made that way from the original C1. All done, I think, by Marshalls at Cambridge.

[Ivan aromer]

The DC8-63 a stretch too far?
757-300 ditto

[DaveReidUK]

I can't think of any other airliners either (which is not to say that there haven't been any).

I suspect that for most types, by the time the manufacturer starts to think of a stretched version there is enough in-service experience to allow them to build the first one as a production airframe, without the need to start cutting at the original prototype.

As far as non-airliner types are concerned, another good example of phyically inserting plugs is also a Lockheed product, the C-141A to C-141B conversion programme.

[treadigraph]

USAF C-141s were all stretched as well.

Not a stretch, but one of Dan-Air's 727s had a different tail grafted on by American Jet Industries.

[Alan Baker]

The prototype Super Constellation was converted from a standard model by inserting the longer fuselage section.

[c52]

The conversion of a fleet is also interesting.

[kcockayne]

Wasn't the Saunders ST27 stretched from a normal size DH Heron ?

[DaveReidUK]

Indeed it was, an 8' 6" stretch if Wikipedia is to be believed.

I remember flying on an Air Atonabee/City Express example in the early/mid-80s.

[dazdaz1]

Some good posts as to 'stretch' of an a/c. Due to constraints of length of airport runways, the longer the a/c length/weight I would presume would require a longer runway.

Gazing into my crystal ball I envisage future a/c will be wider and not longer, having said that, I might be wrong.

[Airbanda]

The F28 Fellowship prototype (PH JHG) was extended from 1000 to be first 2000 and subsequently also flew as 4000 and 6000 with wing/engine etc changes.

[Planemike]

DC 9 grew from abt 105 ft ( -15 ) through to abt 135 ft ( -50 ) and if you count the development into the MD80 series it reached 155 ft ( MD90 )..... Talking length, by the way...

[rog747]

a340-600 is a big one

[treadigraph]

DC-3s and Venturas have also been stretched by companies such as Howard and Basler.

[DaveReidUK]

Kelowna put plugs in half-a-dozen ex-USN C-131s to produce the Convair 5800.

[Scoggy]

The ATL-98 Carvair was a stretched, lengthwise and hightwise DC-4....

[DaveReidUK]

Bombardier stretched the CRJ-700 prototype twice, first to become the -900 prototype and subsequently that for the -1000.

Loftleidir returned some of their in-service CL-44Ds to Canadair in the mid-60s to have them stretched into CL-44Js.

Fokker, on the other hand, shrank the prototype 100 to turn it into the Fokker 70.

[Groundloop]

I think the OP is referring to actual airframes that were cut apart and stretched, not model series that gradually grew in length..

As mentioned by DaveReidUK Loftleidir sent their CL-44s back to Canadair to be stretched from CL-44Ds to CL-44Js. There is an image of the two different lengths here:-

http://images.klassiker-der-luftfahrt.de/sixcms/media.php/11/thumbnails/historische-airlines-loftleidir.jpg.4095706.jpg

and an image of one being cut apart here:

http://www.cl44.com/cl44/images/TFLLGx4.jpg

[Harry Wayfarers]

The DC8-63 a stretch too far?

The DC8-63 wasn't a stretch, it was a re-engined DC8-62, I think you're thinking of the DC8-72 & DC8-73 which were stretches of the latter

[El Bunto]

Several 747-200Bs were sent back to Everett to have the -300's stretched upper-deck fitted. 10% more seats for 2% more weight.

KLM were a big operator, also JAL and UTA. They remained -200s on the type cert, not -300, and were very confusing for spotters...

[pax britanica]

Re the might deisel 8, Super 80 series

there were three models

61, 62, 63

The 61 was for US domestic and had 4 CFM 56s replacing the old coal burners
the 62 was a lesser stretch by some way and had an extended wing as well as the CFM56s and had a very long range for the day -Moscow-Tokyo, LHR-BKK
the 63 had the long fuselage and bigger wing so it had the capcity increase but not the extreme range-it could still do TATL easily enough though

Although not a stellar success I think they were certainly not a stretch too far and both the long and shorter bodies were nice looking aircraft, a lot of both types ended their days as freighters and were very successful until yet another fuel price crisis caught up with them.

Stretches too far in my mind are

737 900, commercial success but apparently a dog to fly and needs very long runway compared tot he 757 it often replaced

Md 90 which really does look like a sort of civilian F104 , all body and no wings

737-300, if you start out with a long single aisle fuselage then stretching it doesnt do much for looks or versatile performance


And for the future-|I cannot see myself up the back on a 777-9X or whatever it is called this week

[pax britanica]

Sorry, re post 21, having expressed a contrary opinion to someone I ought to get my own facts right, it should open
Re the mighty deisel 8 super 60 series

[Airbanda]

The DC8-63 wasn't a stretch, it was a re-engined DC8-62, I think you're thinking of the DC8-72 & DC8-73 which were stretches of the latter

Wrong way round I think.

There were 3 60 series DC8 variants. Firstly the 61, fully stretched but with same power/aerodynamics as 50 series. Effectively high density/medium range. Series 62 was only mildly stretched but had power/wing enhancements for ultra long range. The 63 married full stretch with new wing - high capacity AND long range. All used P&W first generation by pass jets.

The 71/72/73 were 61/62/63 re-engined with GE CF56 high by pass turbofans.

[Harry Wayfarers]

And the DC8 was originally designed to take propellers, that's how they managed to stick fan engines under the wings on the 70 series

[DaveReidUK]

Was the 707 originally designed for props, too ?

[Harry Wayfarers]

I don't believe they ever managed to stick a fan engine on a B707, the wings are significantly closer to the ground ... They had enough difficulties sticking a fan engine on a B737 with the engine's flat bottom.

Apparently the plan was for a propeller DC8 ... right up until the point when they saw the B707 being developed with jet engines.

[c52]

As far as I can tell from Wikipedia, the prop DC-8 had nothing at all in common with the DC-8 that eventually flew. It was to be developed from this oddity: https://en.wikipedia.org/wiki/Douglas_XB-42_Mixmaster

I may say, I've never heard of a prop DC-8 until today.

[Airbanda]

I don't believe they ever managed to stick a fan engine on a B707, the wings are significantly closer to the ground ...

The E3A Sentry is effectively a CFM 56 powered 707. A commercial version, to be known as 707-700 was also flown in prototype form but not developed further. The P&W JT3D and RR Conway were of course fan engines too but with low by-pass ratios compared to today's turbofans. If you look at those machines on ground I don't think CFM56 or equivalent would have needed major modification, perhaps shorter pylons.

IIRC the problem with fan engined 737 requiring the oval nacelle arises because the 73 was designed with low ground clearance to simplify loading/handling at remote/ill-equipped outstations.

[Mad (Flt) Scientist]

I seem to recall being told that Douglas took two damaged DC-9/MD-whatever prototypes, which had been damaged such that there was about one complete airframe left between the two, and "frankensteined" them into one functional airframe. (One of the damaged airframes was the one that had the tail come off during a performance landing test)

The resulting airframe was later used as the UHB testbed.

[DaveReidUK]

The E3A Sentry is effectively a CFM 56 powered 707

As indeed is the US Navy's E-6 Mercury.

[treadigraph]

Around 500 KC-135s were re-engined with CFM-56s as well - while not a direct 707 derivative it is certainly a very close relative!

[El Bunto]

The prototype DHC-8-300, C-GNDK, started life as the prototype -100. Cut & plugs inserted, subsequently scrapped.

Prototype -400 was built from scratch.

[WHBM]

Several 747-200Bs were sent back to Everett to have the -300's stretched upper-deck fitted. 10% more seats for 2% more weight.

KLM were a big operator, also JAL and UTA. They remained -200s on the type cert, not -300, and were very confusing for spotters... This was an operation too far, it was found to be too expensive for the gain in accommodation. It also (like the proper -300) gave an improvement in economy, due to different aerodynamic characteristics of the relationship between the end of the upper deck and the wing root. This had first been identified in the 747SP, which had the same positional relationship between these two.

However the rebuilding, known as the 747-200SUD (stretched upper deck) just cost too much to do. The repositioning of the flight controls coming back from the flight deck was a major part of the issue. I believe Boeing eventually lost a lot of money on the programme, so they didn't offer it any more.

I seem to recall being told that Douglas took two damaged DC-9/MD-whatever prototypes, which had been damaged such that there was about one complete airframe left between the two, and "frankensteined" them into one functional airframe. (One of the damaged airframes was the one that had the tail come off during a performance landing test)

The resulting airframe was later used as the UHB testbed.
Both the prototype MD-80s were seriously damaged in tests, one had the whole tail come off as described (video on Youtube), the other had a different issue (landing gear failure ?), and when it was being recovered on the runway the lifting crane overbalanced and fell across the forward fuselage, cutting it in two.

Not a particularly lucky development programme !!!

[c52]

I recollect that Boeing said they would go ahead with the 747-200SUD if they got enough orders, but they were so pleased with KLM's order, they decided to go ahead anyway. Then practically no one else wanted it.

[rog747]

re the dc 8 super 60 series

the 61 was the longest ever airliner stretch up until then
basically a 50 series with a super stretch

the 62 was a small stretch over the 50 with many upgrades to wing and engines/nacelles with a HGW
the 63 was the 61 fuselage with all the 62 enchantments and HGW's

the 70 series was to Re engine any of the super 60 series with CFM56
the 61 series being a big mod to the wing/pylon area

[xetroV]

Not a stretch, but a shrunk: the first Fokker 70 prototype was constructed by cutting some sections from an exisiting F100 aircraft. This was back in the DASA-days, which preceded the demise of Fokker.

Thorough as these Germans were, they wanted to cut, shorten, re-attach and re-calibrate the electrical wires in accordance with the reduction in fuselage length. Fokker engineers suggested that it might be easier to simply create a big loop in the existing wires...

[DaveReidUK]

Yes, I think I might have read that somewhere.

[WHBM]

When it had finished being the prototype 146-100, it was sliced up, had bits inserted and was fastened back together again to make the prototype 146-300.A previous Hatfield prototype (as the 146 was) had maybe given experience in this area.

https://www.google.co.uk/search?q=de+havilland+albatross+broken+fuselage&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjH-sf3p9jSAhVHPRoKHUfmA80Q7AkILQ&biw=1366&bih=651#imgrc=t8rKVeICqTU3qM:

I understand the repairs took just a few weeks.

[pax britanica]

Rog 747

You are of course quite right correcting my earlier post on the great DC8 stretches. Of course the stretch and wing improvements produced the 60 series and the CFMs were a later enhancement making it the 70 series