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Qantas ferried an engine on the wing of a 747 (2016)

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Re: Qantas ferried an engine on the wing of a 747 (2016)

#51

Post by jsjohnst »

StillBored wrote: post #7

Ok, given its flying just the core, and not the fan, why doesn't it fit in the cargo hold? I mean they wouldn't have to worry about the extra drag/etc in the hold. It also seems odd that they would do this on a plane carrying commercial passengers since it seems more of an "experimental" modification even if the manufacture has approved it.

The issue is the dimensions of the cargo doors. A 747 engine is approximately 2.25m in diameter and 5.5m long. Of the 4-5 different sized doors on a 747, there’s only two that it would fit through:

- Front nose cone door

- Main deck cargo door

I believe neither would be used on a passenger airline configured 747 (could be wrong though!) and hence why the wing based fifth pod configuration was likely used.

Re: Qantas ferried an engine on the wing of a 747 (2016)

#52

Post by usrusr »

roelschroeven wrote: post #37
olliej wrote: post #4

Isn't that an intended standard design use of a 747?

Yes, absolutely. I don't see why this is noteworthy, the 747 was specifically designed to be able to do this.

I'm just surprised they didn't go all the way and solve the apparent drag issue that forces them to remove the fan by making that fifth pylon sufficiently operational to fly the extra engine powered, running at some very low throttle level.

I know the answer, which is that the fan and the turbine are very much separate entities and that removal of the fan blades is a long shot from taking apart the complete engine, but a more gut level part of my brain still likes to consider the entire pod "the jet engine", and from that point of view it feels as if they'd strip out 90% of "the engine" when in reality the entire turbine remains untouched.

Re: Qantas ferried an engine on the wing of a 747 (2016)

#53

Post by nixass »

dotancohen wrote: post #12
leeoniya wrote: post #8

Earlier quoted context omitted.

> Worse things have been carried under wings.[1] this one [1] was way scarier, imo D: [1] https://en.m.wikipedia.org/wiki/1961_Goldsboro_B-52_crash

Though interesting, this is completely OT to this discussion.

No post body was provided.

Re: Qantas ferried an engine on the wing of a 747 (2016)

#54

Post by jsjohnst »

hef19898 wrote: post #21
sreevisakh wrote: post #13

Earlier quoted context omitted.

It isn't experimental or unique even if it's rare. It has been done before. I'm not sure why this instance alone got such attention. Regarding the cargo hold problem, the aircraft wasn't carrying just the engine core. The 'pod' is most likely the engine nacelle itself. I wonder if the entire thing would fit through the cargo door (mere speculation). While it's true that the 747 was originally meant as a cargo carrier…

Normaly the nose loading is done oy when absolutely necessary. It's a pain, takes ages and is complicated. When possible stuff is squeezed through the fuselage cargo doors. Back the day we did it with a ten foot sea container, never thought it would fit...

> Back the day we did it with a ten foot sea container, never thought it would fit

How’d you end up doing it? Roll it on its side? Usually the height of a sea going container is ~2.6m and per the specs I’m seeing online the allowed height through the nose is only ~2.49m. Because they are just taller than they are wide, spec wise it would fit laying on its side, but still curious when doing it for real if that was necessary.

Re: Qantas ferried an engine on the wing of a 747 (2016)

#55

Post by jsjohnst »

sreevisakh wrote: post #24
hef19898 wrote: post #21

Earlier quoted context omitted.

Normaly the nose loading is done oy when absolutely necessary. It's a pain, takes ages and is complicated. When possible stuff is squeezed through the fuselage cargo doors. Back the day we did it with a ten foot sea container, never thought it would fit...

I agree about the nose loading part. Meanwhile, how does an engine with its nacelle compare to a marine container in terms of dimensions? Would it be easier or harder to load through the fuselage doors? I also assume that they will need a fixture or container for the engine if it was to be loaded into the cargo hold.

Engine is roughly 2.25m in diameter and 5.5m in length. So it would fit through the nose cone door, even with a modest fixture/container, with room to spare.

Re: Qantas ferried an engine on the wing of a 747 (2016)

#56

Post by sofixa »

jsjohnst wrote: post #49
sofixa wrote: post #41

Earlier quoted context omitted.

In general there was a time when supersonic flight was considered the future evolution that will displace the existing tech, like jets displaced propeller aircraft. The Concorde was supposed to be the first one, and it was designed as a general use plane, it wasn't until much later British Airways and Air France thought about marketing it for business/first class "luxury" experience. For a myriad of reasons ( Boeing…

> Boeing failing to make their own supersonic airliner which helped the US Congress banning supersonic flights over the US being one of them You sure about that order? I thought supersonic domestic flights got banned in the US and then the Boeing supersonic airliner was doomed. I’m not positive, hence asking.

Nope, government funding of Boeing's SST was cut in 1971, while the SST ban over the US was enacted in 1973. It's fairly certain that had Boeing made an SST there wouldn't have been any ban.

Re: Qantas ferried an engine on the wing of a 747 (2016)

#57

Post by loloquwowndueo »

Animats wrote: post #2

No big deal. External payloads seem strange, but 747s have carried much larger ones, such as the Space Shuttle. Worse things have been carried under wings.[1] [1] https://en.wikipedia.org/wiki/2007_United_States_Air_Force_n...

The 747 had to be adapted/modified to carry the shuttle, but the fifth pod to carry a spare engine was built in on some 747 models.

Re: Qantas ferried an engine on the wing of a 747 (2016)

#58

Post by delsarto »

rkagerer wrote: post #33
bragr wrote: post #23

Earlier quoted context omitted.

The 737-200 had an optional gravel kit for unpaved runways! A few -200s still in use because of that feature

Neat - kind of like mid flaps for planes. Also thank you for teaching me a new word, "cromulent".

I am dating myself but I'm old enough to have watched the Simpsons episode where this word was invented in its first airing. Maybe it is a word now, I mean it's no more or less ridiculous than other words, which somebody just made up at some point too.

https://www.merriam-webster.com/words-at-play/what-does-crom...

Re: Qantas ferried an engine on the wing of a 747 (2016)

#59

Post by newsclues »

EdwardDiego wrote: post #10
sreevisakh wrote: post #6

The ill-fated Boeing 747 flight AI182 (Kanishka) was carrying an extra engine just like this, when it was destroyed over Atlantic ocean by a terrorist bomb attack in June 1985. The presence of the extra engine was investigated as a possible cause of the disaster before conclusive evidence of a bomb explosion was found. (That and another explosion on the ground at Narita, Japan in a container destined for another Air…

Wow, "Canadian Sikh terrorists" was not something I was expecting to read about today.

It’s funny because the Canadian leader of the federal NDP was pretty reluctant to blame the terrorists who did this…

https://www.theglobeandmail.com/amp/opinion/article-the-stra...

Re: Qantas ferried an engine on the wing of a 747 (2016)

#60

Post by waqf »

rzzzt wrote: post #29

I have never heard or read the word "cowling" before, but just finished watching a video saying that Apple's repair guide refers to the tiny metal covers within the phone this way. Cowling cowling cowling.

Ducks have ducklings, so naturally, cows have cowlings.
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