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Sea Witch
03-04-2012, 09:13 AM
My MC is an Air Force pilot from the WWII era.

I would like for there to be in incident in the 1950's when he's flying and something goes wrong creating 1) rapid depressurization and 2) difficulty controlling the plane (but eventually landing it).

Can any of the pilot/engineer/aeronautical/military types here please tell what could cause those two things? Could one problem cause both or do I need 2 different problems. This is not a plane under enemy fire.

Thanks

Hallen
03-04-2012, 09:43 AM
The obvious answer is loss of the canopy. An F-015 would be appropriate if this is happening after 1955 or so.

This is a cool page out of the manual for the Thud that talks about the pressurization settings. http://books.google.com/books?id=Y6ylVunIVVwC&pg=SA4-PA4&lpg=SA4-PA4&dq=F-105+cockpit+pressurization&source=bl&ots=pMQAM4gEIF&sig=ij-AtjoddFZ8o6QrAYhrPmI4u6Y&hl=en&sa=X&ei=6_dST4fTKoaSiAKPuNm1Bg&ved=0CCoQ6AEwAQ#v=onepage&q&f=false

Loss of the canopy is going to cause problems and make the aircraft difficult to fly simply by making things really hard on the pilot. Better hope he has his vizor down and oxygen mask on. About 25k feet, you only have about 5 minutes of rational thought before Hypoxia turns you into a drooling gibbon.

Drachen Jager
03-04-2012, 10:36 AM
Didn't the pilots just wear masks in those days? I know cabin pressurization existed, but for most combat aircraft it wasn't in use. Mostly only airliners had pressurized cabins.

I'm pretty sure if you're talking about a fighter that there simply weren't any with pressurization at the time. It was still a pretty new thing for production aircraft in 1950. I guess it depends on whether you're talking early or late '50s.

Snick
03-04-2012, 05:58 PM
Is he still in the Air Force, or is he flying a civilian airplane? What are the circumstances, and is he flying a jet or a prop plane?

Sea Witch
03-04-2012, 05:59 PM
Thanks all.

No, not a fighter plane. Late '50's, transport plane.

Sea Witch
03-04-2012, 06:07 PM
Is he still in the Air Force, or is he flying a civilian airplane? What are the circumstances, and is he flying a jet or a prop plane?

Still in military, flying military transport plane, based in Guam. I don't know all the types of planes there were during that era, so I don't know what kind of plane he's flying.

robjvargas
03-04-2012, 06:54 PM
A transport?

All transport planes that I can think of from that era don't have an atmospherically isolated cabin. The cabin doesn't depressurize unless the whole plane loses pressure.

WriteKnight
03-04-2012, 09:14 PM
You're looking for the C-133. Large, pressurized. Good article here.

http://www.airspacemag.com/military-aviation/The-Curse-of-the-Cargomaster.html

Snick
03-04-2012, 09:52 PM
I don't know anything about the C-133, but if it was fully pressurized, then having a door fall off would depressurize it and maybe make it harder to fly, at least until the pilot figured out what happened and compensated.

Hallen
03-05-2012, 01:20 AM
As with accidents and failures, just about anything can happen. A door coming off and hitting a control surface or engine or prop will cause an explosive decompression and will obviously cause difficulties for the pilot. The original pressurized jet airliner, the Comet, had several catastrophic failures due to the pressurization. The had used square windows and the corners in the windows caused stress risers which caused cracks when the cabin pressurized. Eventually, the cracks caused massive failures and the Comet turned into a meteor.

Explosive decompression is unpleasant to go through, it's loud and scary, but won't kill you. I've been through the simulator for this in a pressure chamber. As long as you get your mask on in a few minutes, you'll be OK.

Research the aircraft you're going to use to make sure it actually is pressurized.

Sea Witch
03-05-2012, 09:54 AM
Okay that's great, thanks.

One more question. If we're talking about a C-133, what happens if one of the other folks, say the navigator, is injured, unconscious and doesn't get his mask on. Can he survive while the pilot is descending?

Drachen Jager
03-05-2012, 10:24 AM
Depends on the altitude. Probably someone else would put his mask on for him though, unless they were unaware of his condition for some reason.

Sea Witch
03-05-2012, 08:09 PM
Depends on the altitude. Probably someone else would put his mask on for him though, unless they were unaware of his condition for some reason.

Would the mask reach him (the unconscious one) if he's prone on the ground?

Edward M. Grant
03-05-2012, 08:42 PM
Explosive decompression is unpleasant to go through, it's loud and scary, but won't kill you.

So long as you're strapped in. Many of the passengers in the Comets were badly injured or killed before the plane broke up because they weren't wearing seat belts and hit things in the cabin.

AFAIR that was one of the earliest indications that decompression had caused the breakup.

BillPatt
03-05-2012, 11:45 PM
Must the depressurization be caused by a component failure on the aircraft? Canadian geese have been seen flying up at 25k. Have the goose go through the windshield, go between the pilots and whack the flight engineer. Really effs up the crew (though not all of them). Plane gets tough to control with a whole planeload of air rushing out through the cockpit.

The goose could impact the flight engineer's station, changing a lot of the switch settings. The plane could end up pumping all of its fuel to one side of the craft, screwing up the balance, or from front to aft, changing the center of gravity. Be inventive! Have the fire extinguisher go off in one engine but not the other. That affects the flight immediately, and the fuel shift would show up minutes later. It could take chapters to get the plane fit to fly again. With the flight engineer blinded, he would have to get things described to him, and he'd have to figure out the right answer. Good times.

Drachen Jager
03-06-2012, 12:13 AM
Aircraft are designed to handle goose-strikes. Only the engines cannot be properly protected. The angle and thickness of the glass would prevent one from penetrating.

And it's Canada Geese. They don't have passports so they aren't Canadian.

DreamWeaver
03-06-2012, 01:59 AM
Actually, I've seen wing leading edges and radar domes take quite a bit of damage from Canada geese--but damage in these areas doesn't cause decompression. As Drachen Jager says, the real danger is losing one or more engines.

I'd even further qualify that to say, losing one or more engines during a critical phase of flight, such as takeoff or landing. Losing an engine (or even two on a four engine plane) at cruise is typically readily handled by standard emergency procedures, assuming nothing else has gone wrong. Of course, something else often goes wrong. Emergencies are prone to cascade.

My dad once landed a B-52 on three engines, which doesn't sound like much until you realize that means five engines weren't working.

BillPatt
03-06-2012, 07:40 AM
True, aircraft TODAY are engineered to handle goose strikes. But I believe the setting is the 50s, with less knowledge about the hazards (like those Comets mentioned earlier). I'm not too sure how angled the windshield is on those bulky transport planes. The windscreen is only as strong as the frame holding it on. How many times have those failed?

A quick Wiki check showed this gory pic, where a crane hit a Black Hawk helicopter, penetrating the windshield. http://en.wikipedia.org/wiki/File:IAF_UH-60_after_birds_strike_outside.jpg

Then there's the death of Theodore Freeman: On October 31, 1964, Theodore Freeman was killed when a goose smashed through the cockpit canopy of his T-38 Talon jet trainer. Flying shards of Plexiglas entered the jet engine intake and caused the engine to flameout. Freeman ejected from the stricken aircraft, but was too close to the ground for his parachute to open properly.

Not trying to be a jerk here...just pointing out that birds have actually come through the windshield at times.

Snick
03-06-2012, 07:48 AM
Yes, many planes have gone down from hitting birds. There was one machine that had a habit of losing power when it sucked in birds.

Prophetsnake
04-16-2012, 06:15 AM
There are still aircraft losses due to bird strikes. A 737 had a windscreen failure when it hit a hawk and it killed the captain outright.
Here's a link to a presurisation accident of the type you've envisaged ( except nobody saved this airplane)

http://en.wikipedia.org/wiki/Dan-Air_Flight_240

The HS 748 wasn't used by the US military, but this will give you a feel for the sort of things that can happen.

Another interesting accident involving depressurisation is this one.

http://en.wikipedia.org/wiki/British_Airways_Flight_5390

Another explosive decompression that did not end up so well is this one:

http://en.wikipedia.org/wiki/Japan_Airlines_Flight_123

This is, of course, a more modern aircraft, but similar damage would have been inflicted on, say a Lockeed Constellation or a C-97 of the period you speak of with a failure of this sort.

You really ought to read "Fate is the hunter" by Earnest K Gann to get a feel for aviation in that period. He flew DC-4s at the end of his flying career. It's a brilliant read for anyone, too. A best seller in its day..

Prophetsnake
04-16-2012, 06:23 AM
Ooops made an error with the 737 bird strike. The captain was injured, not killed.
There was a Lear that had a failure which killed a crew member a good long while ago, though. I've seen photos of it and it was very messy.
Also, as far as depressurization goes, you could do worse than check out the history of the DeHavilland Comet airliner. They lost two due to fatigue cracks resulting in depressurization.
Control after the event could be lost due to a portion of the airframe jamming a control run, or severing hydraulics, if the aircraft relies on hydraulics for control. IIRC the Constellation did, but the Douglas aricraft used mechanical controls with aerodynamic assistance ( known as servo or balance tabs, depending)

Anaximander
04-16-2012, 05:02 PM
Also, as far as depressurization goes, you could do worse than check out the history of the DeHavilland Comet airliner. They lost two due to fatigue cracks resulting in depressurization.
Technically it wasn't the depressurisation that downed the Comets - a large part of the problem was the rapid propagation of the fractures across the fuselage skin, causing the aircraft to break apart. That's not going to happen on modern aircraft; they're built differently. Metal fatigue and pressure effects at altitude weren't really understood in the days of the Comet 1. The absolute worst you'd get these days is probably something approaching the old Aloha 243 incident (http://en.wikipedia.org/wiki/Aloha_Airlines_Flight_243).

Prophetsnake
04-16-2012, 09:21 PM
Well, without going into boring detail, the pressurization was the reason the fatigue cracks started in the first place.Square windows instead of round.
But the Aloha is a better example, allright. The comet ws period, which is why I mentioned it.
Jimmy Stewart was in a film, can't remember the name, which told the comet story ( though they made a fictionalized airplane called the Reindeer, IIRC.)