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To: jwparkerjr

“I don’t know the specifics, but from my understanding most modern fighters are virtually uncontrollable once they’ve lost all power. The good ol’ days of control cables are gone, replaced by hydraulic systems that require power to operate.”

Thanks for the explanation. I was trying to figure out why he didn’t turn out to sea and eject over the Pacific.


20 posted on 12/11/2008 6:20:47 AM PST by shaft29 (Just your typical black woman.)
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To: shaft29
You have two things to be concerned about when it comes to controlling your aircraft. Altitude and airspeed. You can trade one for the other, but you simply have to have one or the other available if you are to dictate where your airplane goes. The pilot was apparently on final approach to the runway. The normal approach leaves you with precious little of either airspeed or altitude. One report says the crash was about a mile or so from the runway which means the plane was already low and slow when the engine failed. Of course it's possible power was lost farther from the airport and the thought was that he could glide far enough to make the runway. That's not real likely though since the glide ratio, how far you can glide from any given altitude, is pretty much set in concrete. I don't know what it is for an F-18 but I do know that for many general aviation airplanes it's in the 10 to 1 range, meaning you can glide 10 feet horizontally for every foot of altitude. So, for instance, from 1000 feet altitude you could glide about 10,000 feet or two miles. But that's only if you have the knowledge and ability to trim the aircraft for the optimum glide and that involves things such as landing gear and flaps. It's unlikely you would ever really obtain the optimum ration as shown in the manual. Wind direction and speed also have a direct, and potentially devastating effect on how likely you are to reach a particular spot from any given altitude.

You have to keep your airspeed high enough to prevent the wings from simply losing so much lift that you fall out of the sky, never a good result. It's call ‘stalling’ and has nothing to do with the engine, but rather the wing's ability to continue to produce enough lift to keep you in the air. For this particular fighter I suspect the minimum airspeed to avoid a stall is probably something approaching 140 mph. Even it's a bit slower you need some additional speed if you plan to do any sort of turning, etc.

As airspeed falls and approaches the stall speed you can lower the nose of the plane to gain airspeed, but that's done at the cost of altitude. So, if you have enough air below you then you can keep your airspeed high enough to glide quite a ways. U2’s have been know to glide close to a thousand miles when they lost power at their normal altitude of 60 or 70 thousand feet. I'm not sure about those numbers, but they can glide a LONG way from their normal operating altitude.

If he was on a 10 or 15 mile final approach he had neither airspeed or altitude to spare. The plane was going down and he would have little discretion as to where and when short of nosing over and crashing on purpose.

Pilots with as much experience as you get from being where he is an flying what he's flying pretty much know how far they can get without power. Approach paths to most airports are over populated areas and if a plane goes down it's going to hit a house or some other structure.

The pilot would delay punching out as long as possible even if he knew the crash would be into something on the ground. The higher he leaves the plane the wider the area for the crash. Short of having a large, relatively clear area to crash land the crew of a fighter is not going to survive a crash or a crash landing. It's suicide to stay with the aircraft until impact.

So, depending on what went wrong, and where it happened in relationship to the runway, he had at best only a few choices and at worst no choice other than to get out of the plane and save himself.

My heart really goes out to him. And especially to Mr. Yoon.

23 posted on 12/11/2008 6:44:07 AM PST by jwparkerjr (God Bless America!)
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