okay so my cousins and i debated this for about 20 mins after coming back from the airport and it was 3 against 1 that it can.. can it? If planes can reverse, can't it also stand still in the air (w/out falling) if it's accelerating at the right speed? Is it possible?
2006-08-11 07:24:02 · 19 answers · asked by cindy 1 in Cars & Transportation ➔ Aircraft
I think your idea of "reverse" maybe incorrect.
As far as standing still in air, it is quite possible. Although not likely in a large aircraft, small Piper Cubs can actually fly backwards with enough headwind. Let's just say this plane has a stall speed of 50 knots. If you flew directly head first into a 50 knot headwind and kept the indicated airspeed at 50 knots, the plane would have a groundspeed of zero, not traveling forward in relation to the ground. If the headwind increased above 50 knots, the plane would in fact travel backwards. This would hold true for any airplane, but the larger the airplane the higher the stall speed (generally speaking) necessitating a faster headwind.
Reversing the thrust from a turbofan or even reversing the pitch on a propeller aircraft would not help you fly backwards. It would only cause your airspeed to slow rapidly. Many planes automatically inhibit this function in flight.
2006-08-11 07:37:17 · answer #1 · answered by sc0tt.rm 3 · 3⤊ 0⤋
Planes can't actually reverse direction or go backwards horizontally.
An aerobatic plane with enough horsepower can fly like a helicopter for short periods of time.
Also it can "fly backwards" in what is called a tailslide. I can tailslide for about 500 feet but some of the top pilots can hold their plane still and actually tailslide well over 1000 feet so it actually is flying backwards.
A small light plane can tip the nose up at full power and seemingly stop but will end up in an accelerated spin.
An airplane can track backwards against the wind if the wind is moving faster than the plane's indicated airspeed then the groundspeed can be negative.
But for an airplane to reverse itself in normal flight is not possible.
2006-08-11 15:21:06 · answer #2 · answered by beedaduck 3 · 1⤊ 1⤋
You say, "if it's accelerating at the right speed?". If it is accelerating it isn't standing still.
To answer your question, no. Aside from helicopters and some military aircraft nothing is going to hover, and certainly nothing normally thought of as a commercial airliner.
Some aircraft engines have thrust and/or fan reversers. In a pinch, they can be used to back the aircraft while it is on the ground (I have done this on a few occasions) and they are routinely used to slow the aircraft on landing. However, on all the aircraft I ever worked on, reverser deployment in flight is not desirable. It is so undesirable, safety switches are used, normally on the landing gear, to insure there is weight on the wheels before the reversers can be opened. It is simply an interlock situation similar to the interlock on your car that prevents you from starting unless you are in Park or Neutral. Or, in the event of a standard transmission, the clutch is depressed.
BTW, propeller driven aircraft frequently are configured so the props can be reversed also. Again, to back the aircraft on the ground only, and to reduce speed on landing.
2006-08-11 17:50:28 · answer #3 · answered by gimpalomg 7 · 0⤊ 1⤋
absolutely! I have actually taken off in a J-3 cub into a strong headwind, climbed to 500 ft above the ground and adjusted airspeed and power to the point that the aircraft ceased forward progress over the ground and stood still in the air while maintaining altitude, I then further reduced airspeed and drifted backwards past the point of take off and for the finale reduced power to land at the same point I began my takeoff roll. This is something that many cub pilots have recreated over the years and it is an excellent demonstration of aircraft control.
Many whom have been to Oshkosh or Sun-N-Fun have seen the Helio STOL aircraft perform the same routine if winds were sufficient.
Nearly any aircraft with a very low stall speed can be flown in slow flight into a strong headwind with these results.....try it yourself at a safe altitude make your pitch and power adjustments slowly and give it some time maintain that heading into the wind and use your rudder pedals to keep the wings from dipping, watch the ground and you will be surprised at what you are capable of.
I think it would be a blast to demonstrate this off a carrier deck underway with a J-3! I'll bet Steve shares my seintiments....
2006-08-11 16:13:02 · answer #4 · answered by pecker_head_bill 4 · 3⤊ 0⤋
Cindy,
No one has given you a thoiughtful answer so far, so I'm your knight in shining armor:
Apologies to sc0t-----
Yes, a conventional plane can "stand still" AND even fly backwards. This occurs when the plane is facing a wind whose speed is greater than the plane's forward speed through the air. True, generally speaking, most airplanes fly (even at their slowest) at speeds which are greater than the average wind speed, but exceptions to this generality abound. I myself have taken off into a strong wind with only a few feet of ground roll and an angle of climb close to 90 deg with virtually NO speed over the ground. In retrospect, this was a poor decision, but in those days I was invincible.......
Contact me if you'd like more info........
to P/H: (see below)--- You bet I do!
2006-08-11 14:42:59 · answer #5 · answered by Steve 7 · 3⤊ 0⤋
actually if a plane is moving at 300 mph north bound and there is a south bound wind of 300 mph then yes ground speed would be zero but all the same laws of physics must be met in order for the plane to fly. That is why a plane can not fly in a vacuum and that is why commercial airliners fly above the weather.
2006-08-11 14:33:45 · answer #6 · answered by Crockett 3 · 2⤊ 1⤋
It's all a matter of perspective.
The airplane stays in the air because the air flowing over the wings give it lift. Typically the air flow is accomplished by moving the airplane quickly through the air. (ie the airplane move forward).
If you could get the air to move fast enough over the wings, then theoretically yes and airplane can "stand still" in the air.
2006-08-11 14:37:00 · answer #7 · answered by hsueh001 5 · 1⤊ 1⤋
The only 'plane' that I know of that can do something like this is the V-22 Osprey. It has tilt-rotors, & essentially becomes a helicopter in mid-flight.
I don't think that any non-military craft does that.
OH - that's right, akebhart. The Harrier Jump Jet too!
2006-08-11 14:31:45 · answer #8 · answered by Shadow 7 · 2⤊ 1⤋
Yes...the amreican have what is called a VTOL(Vertical Take Off and Landing) airplane called the Harrier. It can hover(stand still in the air) much like a helicopter.
2006-08-11 14:31:00 · answer #9 · answered by akebhart 4 · 3⤊ 1⤋
An airplane gets it's lift from airflow if there is no forward momentum there is no airflow. W/ the exception of planes like the Osprey w/ has propellers and a wing that rotate so technically it's a helicopter when in hover mode
2006-08-11 14:30:14 · answer #10 · answered by Anonymous · 2⤊ 3⤋