Unlimited Vertical
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Unlimited Vertical
I once heard from someone I tought knew a good bit about airplane physics that you needed twice the amount of static thrust as the weight of your airplane to get unlimited vertical. I can understand where it would be helpful, but think it is a bit overkill. Anyone with answers would be helpful because I just can't make sense of it. I have a little less than 5 pound plane with over 7 pounds of thrust, and according to the laws of physics this should do it, I think.
Crashman
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unlimited verticle
Have several planes that fit the bill, they are performance types that need lots of power to pull out of situations that less power would result in a crash. Don,t know the formula just know when I went beyond the minimums by a healthy margin. TRY IT YOU'LL LIKE IT.
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Unlimited Vertical
Crashman,
In theory, you can hover at full throttle if you have as much thrust as weight. But in reality, you need to make adjustments and corrections. For example, you might want to reduce power to lower the plane to ground level. Once it starts descending (in a hover that is), you will need thrust in excess of it's weight to stop the descent. Then when you want to "pull out". You would use full power and accelerate upwards.
Of course, the plane could "tip over" while hovering and you need to get going real fast. That is where gobs of power comes in handy.
Tom
In theory, you can hover at full throttle if you have as much thrust as weight. But in reality, you need to make adjustments and corrections. For example, you might want to reduce power to lower the plane to ground level. Once it starts descending (in a hover that is), you will need thrust in excess of it's weight to stop the descent. Then when you want to "pull out". You would use full power and accelerate upwards.
Of course, the plane could "tip over" while hovering and you need to get going real fast. That is where gobs of power comes in handy.
Tom
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Unlimited Vertical
7 lbs. of thrust, 5 lbs. of plane,? You are in the green my friend, as you will have unlimited vertical, hovering may be another story.
Jetts
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Unlimited vertical
Hi all,
In normal level flight, thrust is needed to overcome drag (move the airframe) and lift is needed to overcome gravity (weight of the airframe). In vertical flight the wings are not producing lift, so thrust alone is needed to overcome gravity and drag (acting in the same direction now).
If the thrust equal the weight of the airplane it would still not have unlimited vertical. After the initial pull to vertical the inertia of the airframe will add to the thrust of the engine, but drag will overcome this advantage until the plane stops. For it to keep going up, we need enough thrust to overcome the weight and the drag of the airframe combined.
Does this make sense?
Willem
In normal level flight, thrust is needed to overcome drag (move the airframe) and lift is needed to overcome gravity (weight of the airframe). In vertical flight the wings are not producing lift, so thrust alone is needed to overcome gravity and drag (acting in the same direction now).
If the thrust equal the weight of the airplane it would still not have unlimited vertical. After the initial pull to vertical the inertia of the airframe will add to the thrust of the engine, but drag will overcome this advantage until the plane stops. For it to keep going up, we need enough thrust to overcome the weight and the drag of the airframe combined.
Does this make sense?
Willem
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Unlimited Vertical
For unlimited vertical, you need about 150% of the planes weight in thrust. You have to overcome the weight of the plane and the drag of the air on the plane. If you are going to do any snaps or maneuvers on the up-line, you have to have thrust to overcome that drag as well.
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Unlimited Vertical
Thanks again guys. the advice should prove handy. this is my real first attempt at doing aerobatics, so hovers and vertical snaps are a little away yet, I know that to pull out of a hover you need to have a heck of a lot of excess thrust. Now I just want vertical. In time i would like to try 3d, but will need a bigger plane. I'm just gettin started though, and will also need a lot more rates in the current plane to pull off anything really fantastic, and i dont have expo or dual rates. the plane is a CAP 232, and should perform moderately well, i klnow not competition level, but its a start.
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You don't need that "nasty" power to do basic aerobatics. None of my planes have unlimited vertical and I fly lots of aerobatics. I really enjoy seeing a plane fly smooth conventional maneuvers.
Tom
Tom
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That is very true. THe only benefit I have seen with unlimited vertical and aerobatics is that many of your up-lines maneuvers can be entered in slowly because you don't need the speed to get the vertical hight. Having UV allows you to recover better if you enter them poorly.
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Not only do you need enough thrust to overcome weight and drag, but also MOMENTUM, you can fall backward pretty fast sometimes. Realistically, the TOC guys are aproaching a 3 to1 thrust to weight ratio. THAT IS 300% of the planes weight. They hover at just BARELY over idle, then they lift off like the shuttle. The use of the throttle will keep the plane from looking like it has this rediculous amount of thrust.
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Unlimited Vertical
Originally posted by CAPtain232
... Realistically, the TOC guys are aproaching a 3 to1 thrust to weight ratio. THAT IS 300% of the planes weight. They hover at just BARELY over idle, then they lift off like the shuttle. ...
... Realistically, the TOC guys are aproaching a 3 to1 thrust to weight ratio. THAT IS 300% of the planes weight. They hover at just BARELY over idle, then they lift off like the shuttle. ...
Mike