B52 Crash Video's

Some of the early videos implied they had retract problems. I saw the single outrigger too. The other one simply did not come back down for landing. I'm sure that happened to the real one on occasion.

One thing I noticed in the crash video was the wheels retracted quick and clean. Looks like they had that problem solved anyway.

Reply to
C.O.Jones
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You're right but, the air mass is not static. And as the plane changes its orientation relative to the air mass, things happen. That's my point. Are you suggesting that as the planes orientation changes and the surface area exposed to the various currents of air, the various forces the controls must over come will not change?

Reply to
C.O.Jones

Now force the balloon to change direction so it's no longer directly with the wind. Isn't that what a turn does? Isn't that what that B-52 was attempting to do? As long and relative position in the air mass stays the same, I agree with you guys. But once the relative position of the plane to the air mass starts to change, things happen.

Reply to
C.O.Jones

Don't factor in ground effect/turbulence into the basic argument, or everything goes out the window in a hurry. It is called chaos and is quite capable of reducing our largest computers to blithering idiots in a hurry. I am not saying that there are not such effects in nature, but they are separate from the basic issue of relative wind.

When I first began flying models that were capable of flying at extremely low airspeeds, I ran into a phenomenon that I had never encountered before. I could be flying along at minimum sustainable airspeed, dead into the wind, and suddenly the model would simply fall out of the air. Fortunately, I was usually dragging the model around at one or two feet off of the ground when this happened, so there was usually no damage.

It then occurred to me on several occasions that just before my model fell and when I was directly upwind of the model, I had felt a swirl (vortice) of air go by my body. The model ran into the downwind side of the vortice, the wing ceased to fly and the model fell to the ground. I was astounded. I had been flying R/C for well over twenty years and had never encountered this phenomenon with a conventional model. Why? Because conventional models fly so fast, relatively speaking, that the effect was unnoticable.

Ed Cregger

Reply to
Ed Cregger

... | > I think the point you're missing is that the actual airplane wing is not | > attached to feet planted on the ground. Once the aircraft is in the air, | > it is a part of the air mass, not the ground. | | You're right but, the air mass is not static.

Assuming a smooth, steady wind (which is a relatively reasonable assumption once you get away from the ground and the turbulence and wind gradient it creates), the air mass *is* static if you're in a point of view that is moving with the wind. Which is the one that matters if you're flying a plane in it.

| And as the plane changes its orientation relative to the air mass, | things happen.

No, they do not. Not any differently than they would happen were there no wind at all anyways.

| That's my point. Are you suggesting that as the planes orientation | changes and the surface area exposed to the various currents of air, | the various forces the controls must over come will not change?

The plane will not fly differently. It will only seem to fly differently, and because of that you might give it different stick inputs, making it fly differently `for real'.

If you move a control surface or increase throttle or something, your plane will cause various air currents and things will change, but no differently (from the plane's point of view) than they would if it were flying in calm air.

It's all in your perception ... and once you realize this, and start taking it into account when you fly, you'll probably become a better pilot.

Reply to
Doug McLaren

Remember thre downwind fish? Thought so. Unless an airfoil has eyes, it is blissfully ignorant of which direction it is proceding relative to the ground. Upwind, downwind, crosswind it moves with the airmass. UNLESS the airmass changes direction or speed so rapidly that the inertia of the aircraft prevents it from matching it instantaineously. This phenomanon is called windsheer and it has killed quite a few experienced pilots.

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While the above accidents were on take-off or landing, it also happens at altitude. The book "Anvil of the Gods" relates an incident in which a 707 over Florida in the early '60s was penetrating a thunderstorm at FL 350 and got flipped on it's back, split-s'd out of it and landed with an additional 10 degrees dihedral in it's wings. BBBBA!

Reply to
TexMex

True Doug.......with a steady wind to fly in my SS downwind hauls butt, upwind it will hover.

Anyone who is skeptical to what Doug, Paul, and Ed are saying should talk to a flight instructor. Its just a myth.

Mike

Reply to
Mike R

Wind doesn't do that because the airframe is moving with the moving air mass.

Reply to
Paul McIntosh

The plane's engines and control surfaces make it change direction, but only acting upon the air mass.

Reply to
Paul McIntosh

Absolutly right! The O N L Y thing that counts is the relative wind over the wing AS SEEN BY THE WING! In all of the 1:1 scale examples shown previously, the RELATIVE WIND changed almost instantaneously but for some reason some of the PIC's were not ready to react properly. The general rule of thumb I was taught is that when wind shear is reported, carry more knots on final. Easier to ride out the changes seen by the wing. The question becomes how to transfer that to modeling.

When we "see" models stall and crash on the deadly 'down wind turn' we are not seeing a change in physical laws, rather our perspective is confused just enough to "see" something that does not exist. Remember we DO NOT know the true airspeed of any model unless we have a telemetry package. Turning down wind without enough energy is only deadly if you are too low, bank too much, AND pull too much elevator in the turn. Read that as YOU pranged it rather than blaming the resultant crash on mother nature. .

Reply to
Six_O'Clock_High

. Remember we DO NOT know

Do the telemetry pakages offered for models come with a some cool "shades" that would give a HUD display in real time of indicated air speed, true air speed, pitch ladder, velocity vector, and AGL ?? If not, I think it would be a good idea. The ones I seen looks like you can download the info to your PC after your flight.

Mike

Reply to
Mike R

ROFLOL!

No, I don't think knowing the airspeed, AOA, altitude, etc. AFTER the flight is going to do much good. Nor am I aware of a HUD for my glasses. . . .

Reply to
Six_O'Clock_High

Then how do you account for the obvious bumpy ride it had during the climb out after take off?

Reply to
C.O.Jones

You mean that static, unchanging air mass?

Reply to
C.O.Jones

That forces the question of whether or not that B-52 was above ground effect or not? Not the models ground effect but the ground effect of the trees, houses and other obsticals in the area. And that is my point. The air mass was not static nor was the relationship between the model and the air mass.

The formulas are great for the minute slice of time they describe. But that moment is quickly gone and new values come into play.

Reply to
C.O.Jones

Ah, you have forced me into my first concession. Obviously, it was NOT out of ground effects. 8>)

Ed Cregger

Reply to
Ed Cregger

......with all the tech talk right now, someone is going to come up with a micro system that will deliver all this info in real time. The current ones only give you the info post flight.....like a " black box". Some car manufactures are experimenting with HUD..... I know the video systems for the model heli's that are available you can get with video glasses ( FLY RC September issue 2004 pg. 42 ). A bit on the bulky side. Look at the AH64 Apache pilot with the helmet mounted monocle that delivers AOA, AGL, airspeed, ect....still a tad bulky. Would be nice having this info displayed to you while you are flying.........I think very helpful...............not very afterwards.

Mike

Reply to
Mike R

| > > The general rule of thumb I was taught is that when wind shear | > > is reported, carry more knots on final. Easier to ride out the | > > changes seen by the wing. The question becomes how to transfer | > > that to modeling.

Easy. You never know the exact airspeed of your model, so don't fly right down to stall speed. The more uncertain the air speed is (high winds and especially gusts = more uncertainty), the larger cushion you leave when you're close to the ground.

| > Do the telemetry pakages offered for models come with a some cool | > "shades" that would give a HUD display in real time of indicated | > air speed, true air speed, pitch ladder, velocity vector, and AGL | > ?? If not, I think it would be a good idea. The ones I seen looks | > like you can download the info to your PC after your flight.

That would be cool, but I wonder how distracting it would be ...

Actually, there are telemetry systems that use audible signals rather than visual ones. The sailplane guys use them a lot. Typically you have a FRS or ham band receiver and listen to your plane. The simple `varios' will transmit a tone that varies based on if your plane is gaining or losing altitude (just like full scale ones), and the fancier ones have speech synthesizers that report speed, altitude, altitude deltas, battery voltage, etc.

| No, I don't think knowing the airspeed, AOA, altitude, etc. AFTER the flight | is going to do much good. Nor am I aware of a HUD for my glasses. . . .

Knowing these things after landing can be very useful. Also, you can buy wireless systems that let you view them in real time. (Not suggested for the pilot, but a spotter could use it ...)

Like this --

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though that's only one system, there are others.

Reply to
Doug McLaren

Yes, but you are not holding one end of a boeing 707 are you?

Prat.

raise it so it is

Reply to
The Natural Philosopher

C O Jones is a tosser, and his mind is small enough for him to beleive anything, including Dubya.

Don't waste yer breath.

Reply to
The Natural Philosopher

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