The L-1011 designed as a twin-engine plane from the start.

It started when I was reading this post on a twin engine version of the L-1011 in another thread:
Actually, what saved the TriStar program was Rolls-Royce offering the much more powerful Trent 700 engine, which made it possible for Lockheed to build a twin-engine version of the plane by 1988. The L-1022, as the plane is known today, built with ETOPS certification in mind and had ranges of 5,600 nautical miles for L-1022-200 longer version and 6,400 nautical miles for the L-1022-100XR shorter version (OOC: it duplicated what Airbus did with the A330), and Lockheed couldn't keep up with demand.

then I watched this video on the L-1011:
In the video, it mentions Frank Kolk's concept for a smaller widebody plane as an alternative to the 747.

So it got me wondering: what if instead of three engines, the L-1011 was designed from the start as a twin engine widebody airliner specifically made for domestic routes in the US? A twin engine design would certainly have some advantages (reduced weight, maintenance and fuel consumption plus fewer restrictions on engine mounting). Would such a plane be possible (or feasible) at the time? Also, could such a plane be more successful than OTL's Tristar?
 
My understanding is that the S-duct meant the L-1011 needed a compact engine compared to the DC-10. Like the 727 it limited it to small engines and further upgrades. In the era I think three-engines made sense, but could the airframe and wings take deleting the tail engine to use bigger more powerful engine wings? ETOPS I think was far enough out that it is not influencing the L-1011, but can we morph it to a 767? And take it further to get an earlier 777? Otherwise I think the suggestion is that maybe we simply need Lockheed to look beyond the market they built for and go fully into a cross ocean platform, building the L-1011 bigger so they compete with 747 and position to be first with a 777 twin jet long range replacement to 747 either earlier of before Boeing gets there. I think L-1011 was too big for domestic and not enough for international, it fell into a niche squeezed from both ends, when it could be competitive other designs were there. But could it have been better used to serve smaller destinations, breaking out of the hub and spoke, like how Southwest served more secondary airports direct, would that get L-1011 viable and now get us its replacement as a two engine?
 

DougM

Donor
As far as I know the L1011 was designed for trans ocean travel that required (back then) 3 or 4 engines to meet federal law. So in order to go with a wide body twin you need a more powerful engine (somehow) and to give up the cross ocean market.
It may be simpler to use a pod of no DC10. I have alwas thought the big issue was that the market was split between two planes and neither had enough sales.

-Doug
 
Even if you went with the airbus (mid-range trunk route) concept instead of the three-engine performance model the TriStar eventually became, you still have a problem with existing high-bypass turbofans of the time. In the late 1960s and early 1970s, 50k lbf of thrust was stretching the limits of engine technology, which was why the TriStar's first RB211s put out only 42k lbf of thrust. Among twinjets of comparable weight to the TriStar, the A330 and 787 have engines in the 65k lbf to 75k lbf range, far beyond the limits of contemporary engine designs. A smaller design meant to find the limits of twinjet capability would essentially turn out an A300 competitor instead of a DC-10 competitor. The US market for the A300 was roughly 200 out of 550 total, which would probably lead to a situation similar to the TriStar's competition with the DC-10 in a market for 600 planes.
 

DougM

Donor
Businesses in general ranging from Hamburger places to aircraft manufacturers and everyone in between have a nasty habit of trying to insert themselves into places someone else already is (or is about to be) in order to make money. The problem is that many times there is enough profit for ONE to do ok but not enough to split.
In this case it is had to say that the market for tri jets at the time was enough for two new aircraft. The same can be said about the twin jets that the engines back in the day would have been capable of.

Today we may be seeing the same issue with SuperJumbo type 4 engine aircraft. It is possible that Boeing could have done a radical overhaul on the 747 ginving it as much updating as they could to make it more efficient and this may have cost a lot less the the A380 but with the A380 eating into the market It was doubtful that the cost could be justified. And the cost of the A380 was so high that the more modern and efficient airframe was hard to justify in the limited market. And with the 747 already in the market it was not helping. So once again two companies compete in to small of a market and both have trouble.

I think that was the huge issue with the 1011 and did not help the DC10. Add in the DC10s troubles and its high profile crashes and I wonder if this helped make McDonold Douglas situation worse.

Now going with a twn would have moved it out of that competition but it would have had other issues. First off not having engines at the time that allowed for it to be a twin unless it is smaller. Then you have the no twins over oceans bit. It also started moving it away from the request that inspired it to begin with. And of course it would not have been the only twn on the market so it would have swapped one competitive market for another.

So short of keeping Douglas out of the market with it’s DC-10 I don’t see any other real options for saving the L1011.
 

WILDGEESE

Gone Fishin'
It started when I was reading this post on a twin engine version of the L-1011 in another thread:


then I watched this video on the L-1011:
In the video, it mentions Frank Kolk's concept for a smaller widebody plane as an alternative to the 747.

So it got me wondering: what if instead of three engines, the L-1011 was designed from the start as a twin engine widebody airliner specifically made for domestic routes in the US? A twin engine design would certainly have some advantages (reduced weight, maintenance and fuel consumption plus fewer restrictions on engine mounting). Would such a plane be possible (or feasible) at the time? Also, could such a plane be more successful than OTL's Tristar?

Apologies beforehand so please feel free to correct me if I have this wrong so here goes.

To have a twin engined L-1011 you need two types of engine.

Firstly for the 767/A300 class aircraft you'd need an earlier development of the same class engines that powered the A300. The A300 flew in 1974, L-1011 flew in 1970. Coincidently Rolls-Royce were going to make this type of engine in the '60's for the BAC 3-11 (A300 style) aircraft but didn't fund it when the 3-11 didn't get UK government funding and the UK aerospace industry were told to join Airbus.

Secondly for a twin engined international L-1011 (747/777/A330/A340) class aircraft you need to some how butterfly away the 747. The original design of the 747 was for the USAF's C-X contract which was won again coincidently by the Lockheed C-5, the aircraft having 4 x 56/58,000lb plus engines. Now if Boeing doesn't go on to develop the 747 it would allow both Douglas & Lockheed to ask the engine manufacturers to develop a 90,000lb engine straight off.

As I said I might completely be wrong about this so correct me if I'm wrong.

Regards filers
 
So it got me wondering: what if instead of three engines, the L-1011 was designed from the start as a twin engine widebody airliner specifically made for domestic routes in the US? A twin engine design would certainly have some advantages (reduced weight, maintenance and fuel consumption plus fewer restrictions on engine mounting). Would such a plane be possible (or feasible) at the time? Also, could such a plane be more successful than OTL's Tristar?

OOC: If I remember correctly, what American Airlines wanted when they released their specification for a smaller wide-body airliner originally was a plane that could fly at least USA transcontinental routes but do it with just two engines. In 1966, that meant either the civilian version of the GE TF39 engine (the CF6) or Pratt & Whitney's JT9D engine, then rated at around 43,000 lb. of thrust. Interestingly, Boeing finally fulfilled that very specification with the 767-200, which entered service in 1982. But American Airlines wanted the ability to fly over-water routes, and that meant the plane needed three engines (this was before the days of ETOPS requirements). The result is the tri-engined DC-10 and L-1011. It wasn't until the 1980's that the ETOPS 180 requirement arrived, and the first twin-engined airliners to get ETOPS 180 certification were the Boeing 767-200(ER) and the Airbus A310-300.
 
Top