The Incredible Boeing 747 Tri-Jet And Why It Failed

Did you know that Boeing had once been working on a shortened, three engine variant of the 747?

Nowadays, it is hard to imagine the Boeing 747 as anything other than a four-engine icon. However, in the 1960s and 1970s, Boeing was considering constructing a three-engine variant of the type. This tri-jet aircraft would have had one engine under either wing, with an additional engine mounted on the tail. This design would have been similar to the narrowbody Boeing 727, although obviously much larger.

Video source links:

Photo source links:

#Aviation #Flight #Avgeek

[Elias-xykc]

If they did it, it might’ve flown nowadays with no big problem and issues on fuel efficiency!

[mann]

Hugely impressive I've found this channel so informative subscribed for 5 Months now

[sethtan]

Actually I thought 747SP meant 747 Short Plane.

[letsseeif]

Had the pleasure of flying as a passenger on the DC10 and B747SP through the eighties. Great memories!

[PujanPatel]

How about a 747 with 2 GE9x engines and the 3rd fuselage mount engine at the back? That's not exactly a bad idea... Something worth considering.
Airlines feel quad jets are too expensive to maintain, twin jets have their limitations so then a tri jet would be the best fit!
I feel tri jets would definitely make a dramatic return in the coming future...

[badhrihari]

Well, it would mean better fuel efficiency

[shrimpflea]

That idea actually came about because several airlines, like Delta complained that the 747 was too big. Which is why Delta started flying the L-1011.
The L-1011 was one the best passenger aircraft ever built IMO. But unfortunately for Lockheed most airlines opted for the cheaper DC-10.

[iliketrainspwned]

So you're telling me a 2 hump jumbo jet was almost a thing?

[Bureaucromancer]

I honestly think killing this was probably harmful in the long-run. The initial tri-jet would have amounted to an overpriced iteration of the SP, but the new wing would have allowed a 747 in place of the ASB as soon as larger engines became available. Effectively, there could have been a 777 at least five years early, but pairing the standard tail with the trijets wings and new engines at the same time the -400 was developed. You'd also have sales driven by the nose-door being avialable on a smaller aircraft than the 747 that would seem likely to, at a minimum, create enough sales to push off any talk of cancelling the program in 2020 and result in the trijet itself selling better than the SP did. I also suspect that without the 777 in play we'd have had a 767 NEO program at some point in the last decade, with considerably more 767-400 sales than we got historically. Given the cultural impact the 747 would have, I wonder if the 787 wouldn't just be a re-winged 767.

Certainly the A350 would look better in comparison to a 747 Intercontinetal Twin Shortbody than it does competing with a 777, but between commonality, cargo options and earlier availability this wouldn't have been a poor seller by any means, and the economics of commercial aircraft being what they are I tend to think that total airframe counts approaching historical while essentially removing a whole airframe development program (or two) from the picture would be a net positive for the company.

tl;dr the trijet wouldn't have sold all that well, but the strategic implications of the new wing and a true family of aircraft with 747 cargo handling would have done a lot for Boeing.

[the_cheese]

If Boeing had gone ahead with the 3-engine 747 concept, I think it would have made the situation at both Lockheed and Douglas even worse in terms of selling jets. The L-1011 and DC-10 programs were competing for a relatively small market space (one that could not, realistically, support both aircraft in large numbers) and the 747-Trijet would've cut the top of the market off of the long-range variants of both competing three-holers, while undercutting the 4-engine 747 as a medium-range high-capacity solution.
This plane would also have had a knock-on effect on the 757 and 767 programs, which likely would not have come about until the 1988-1990 time frame. Great video, Simple Team!

[nighthawkvca]

1:47 - The 747 SP is such a cutie. I like to think of it as the mini-queen 😉

[thefibs]

I absolutely LOVE the way the trijet looks with the 747 hump!

[deeya]

Can they bring back tri-jets to make economical double-decked jumbos? IIRC both Airbus and Boeing has prepared concept drawings on a twin-engined double deck. Mostly encountering the issue with needing too large an engine to make the aircraft feasible. But could it be done with 3?...

With new technology, perhaps tri-jet double decks could be made comparatively feasible to the twinjet single deck, it's all a numbers game after all, capacity over fuel burn. Granted, high capacity double decks are going the way of the dodo due to the switch in travel to point-to-point.

[dhilboy]

Honestly though I'd allow it now if it meant keeping the Queen in operation🙌🏽🙌🏽

[quillmaurer]

My understanding was that this wasn't made because Boeing did enough market research to determine that the market for widebody trijets - this competing with the DC-10 and L1011 - wasn't big enough for a third entry, and hence it wouldn't sell well. The 747-SP didn't sell well either, but cost far less to develop hence was able to break even when the trijet wouldn't have. Seems like a good decision given that there indeed wasn't much market for that segment, the L1011 was pretty much a commercial failure and the DC-10 a moderate success. This is one thing Boeing is pretty good at, analyzing and building what customers actually want, or anticipating what they will want. There's a lot of things they've considered but ultimately never built that in hindsight was a good decision. Larger 747 variants that would have been in league with the A380 - the A380 hasn't been as successful as hoped, good move on Boeing's part to not make that. A passenger jet (707) in a time when nobody else thought that to be the way forward - that's what really put Boeing in the lead. A huge twinjet, designed before ETOPS was a thing but they envisioned it would be - the 777 is doing really well, while the competing A340 has suffered.

[danielgallagher]

I have a friend who piloted the the 747 SP for American. Mostly on the route from Dallas to Japan. He loved the flying characteristics and said it rode out turbulence very well.

[luckyme]

Contrary to the title suggesting the 747 TriJet was a failure, it was indeed a triumphant success and an important tool in the world of AFRM (Airport Fire Resource Management). They don't fly but are a common sight at all major airports and are used primarily for training firefighters in the event of an actual aircraft fire/evacuation event. London's Heathrow airport has one in active use and is affectionately known as the "Jolly Green Giant".

[piyushkanthak]

Simple flying, I have a question, please answer..
Why does your channel have less views likes and subscribers..You people deserve a lot..A million subs., likes and comments..No time waste only on the topic and the best content..

[IntellectualHazard]

Let's just all agree that it'd look *Weird*

[arispelius]

Boeing definitely dodged a bullet. Trijet’s showed there inherent danger in United flight 232 in 1989 when a DC-10 had an un-contained failure of the middle engine that caused all three independent hydraulic systems to fail.

It is just to risky having an engine located in a position like the tail where an engine failure could cause total loss of the use of a critical control surface.