Aug 7, 2007

How Big Do You Want It? - Supersizing the Revolution

The introduction of Boeing's Jumbo 747 began yet another revolution in air travel. Now it became a mass-production game. And hand it to Boeing - they are masters at refining a design so the original B747-100 grew into the dash 400 with a fully electronic, two-pilot flight deck and stretched fuselage.

Along with the size came new hazards to other airplanes and ground crews. After a couple of nasty surprises to following aircraft, NASA began tests to see just what the wake vortices look like behind a 747, and how they affect the runway environment.

Ground hazards also increased with the advent of jumbo engines. Here's one light-hearted demonstration of a very real threat to airport staff and equipment:

But the sheer grace of this much aluminum aviating in close proximity never fails to inspire:

Through the years the fourty-seven has been adapted to many unique rolls - attesting to the basic strength and versatility of the design - such as a Space Shuttle Transporter:

And now a Wing Transporter in support of the B-787 program:

As with any design there have been some tragedies, especially as fleets age and the original safety margins erode. In this case, aging wire insulation failed, setting the stage for a horrific outcome.

Seconds From Disaster - TWA 800:

Nevertheless, just as the B-707 and 727 were the iconic airliners of their day, the mention of the word Jumbo Jet today most likely evokes images of Fat Albert - King of the Sky - the Boeing 747.


Anonymous said...

Maybe you, or one of your readers, can help. Here's a link to a photo of a 747 being towed in a PR shot for a VW 4x4. On closer inspection, you can see that the 747 has a twin engine configuration hanging from the inner engine mounts... I've never seen that before.
Maybe you can shed some light on this special 747? Thanks a lot. Neil

Anonymous said...

Now with link attached!

Klari said...

Awesome videos!
How does having a shuttle on one's back change the flying? How do the pilots train for that?

Aluwings said...

Hey Neil,

I recalled something I'd seen in an Aviatrix blog about the movie Casino Royale - it looks like the same movie prop version of the B747 (i.e. it never actually flew in this configuration.)
Movie B747...

Soaring Student said...

I've never seen that engine configuration before - but there is also some sort of a pod on each of the the outer engine mounts. The bird also has all of the windows, so it perhaps is not of military heritage (I thought the pods might be ECM).

If an engine needs to be shipped from here to there, one method is to attach it to the wing and carry it externally (there are extra hard points under there). One 747 that went down (not sure if it was Pan Am 101 or Air India) was carrying a fifth engine.

Soaring Student said...

Notice that the shuttle-carrying 747 (there are actually two of them) has a different tail - with two rudders out of the turbulance from the shuttle). An empty shuttle weighs "only" about 200,000 pounds, so no issues there. the biggest difference is drag: When flying from California to Florida they have to stop for refueling. They also limit their altitude and speed. They don't fly in rain - not because of the 747, but because the thermal protection tiles on the shuttle are quite soft, and impact with raindrops at 300mph would destroy them.

Trivia: there are three attachment points on top of the 747. But the forward attachment point there is a placard saying "Attach shuttle here, black side down" (close enough, they don't use shuttle, I think they use STS)> There is another label somewhere nearby which says "righty-tighty, lefty-loosey".

Soaring Student said...

OK, forgive the triple post.. The two 747's are called Shuttle Carrier Aircraft.

The label is: "Attach orbiter here. Note: Black side down"

John Hooper said...

I wonder if anyone can help me.

I have a friend who is now a police officer (and should therefore be considered reasonably trustworty) but previously had worked in security at Gatwick Airport.

She told me that in their introductory lectures they were told that there is a fifth engine on a Jumbo Jet which can be deployed in an emergency.

I assumed that this was a sort of "apprentice joke" (like going to get a glass chisel or a tin of tartan paint)but yet another police officer said that there was in fact a small engine that could be deployed. (I forget what he called it but it was a mule or a donkey engine).

Is this true ???

We established that it was some sort of small engine and not a huge Rolls Royce engine like the other four but I am still a bit dubious about this.

Any sensible advice welcomed.

Aluwings said...

Could be the fifth engine carried for transporting:

See this
Look Here

Or this
Or Here

Or perhaps she was referring to the Auxiliary Power Unit (APU)?

John Hooper said...

Thanks for that but she definitely said that it was an engine which could be deployed from either the wing or the fuselage in the event of an emergency.

As I understand it the APU is fixed inside the rear of the fuselage and delivers power to lighting/heating etc.

I could hardly see that there would be room for much inside a Jumbo Jet wing.

It could hardly have one in the fuselage either.

I think the lecturers must have been pulling her leg. A case of ragging the newbies.

Aluwings said...

One last possibility - could be they were referring to the Ram Air Turbine. This is a small wind-driven unit that keeps an emergency generator or emergency hydraulic system operating in case of a total engine failure. (Design varies a little by aircraft type).

Check This

This isn't an engine to provide thrust. But to supply power for the systems the pilot needs to guide/control the glide.

Also consider the possibility that it was a case of "the blind leading the blind." Due to misunderstandings and imperfect terminology, her (or their) understanding of what comprises a "deployable motor" might have caused confusion...?

John Hooper said...

Thank you Aluwings.

That is almost certainly what they were referring to.

It was just the way it was phrased in terms of a "spare engine which comes out in an emergency" which made it sound like a hidden Rolls Royce engine rather than the tiny little thing it actually is (although I suppose it is in fact exactly a spare engine that comes out in an ameregency).

Many thanks for that and may you have many years of boring and totalaly event free flying.