Many modern passenger aircraft can move backwards under their own power, although it is usually not standard practice to do so if a tractor (usually referred to in aviation as a "tug") is available. The aircraft must be equipped with a reverse thrust system. These systems are designed to assist in reducing the aircraft's speed after landing, and in the case of turbo-prop's, also assist in ground manueverability. Many turbo-fan powered aircraft (commonly reffered to as "jet" aircraft) use a reverse thrust system that re-directs the flow of engine exhaust and/or fan discharge airflow. The airflow is directed forward and outward from the rear of the engine, instead of straight backward.
Although these systems are intended only to help slow the aircraft down during landing, the thrust reversers can be deployed when the aircraft is stationary,on the ground. Apply enough throttle and sure enough, the aircraft will move backwards. I do stress that this is not the recommened practice, for many reasons. First, the pilot cannot see what is behind the aircraft, so ground crew must assist and provide direction. Secondly, because the discharge airflow during reverse thrust is directed forward of the engine, it has the tendancy to stir up debris (small rocks, etc) from the ramp area, which can be ingested by the engine, causing substantial (and expensive!!!) damage.
It is common practice, however, to use reverse thrust on turbo-prop driven aircraft, on the ground. The engines don't spin backwards, as one user suggested, but instead the pitch of the propeller blades are changed to redirect thrust forwards of the aircraft. The plane must be equipped with adjustable pitch propellers, with "beta range" (reverse pitch) capability. On multi-engine turbo-prop's, using reverse thrust on one engine and normal thrust on the opposite engine will actually assist the pilot in making turns, on the ground. Again, if the aircraft is stationary on the ground, putting the propellers in reverse thrust pitch will indeed cause the plane to move backwards.
2006-06-18 08:07:47
·
answer #1
·
answered by Anonymous
·
4⤊
0⤋
Most aircraft can go backwards on there own, but there are only a few that do it on a regular basis. The DC-9 and the MD-80 are two of the more common ones now. They have two engines on the tail on either side. At MSP, the only reason they bring in a tug for the DC-9 is if it's a tight turn. All other wing mounted engine aircraft have the capability, but due to the proximity to the ground, its not recommended. Some places, it is common place to see it, but they have certain tight restrictions. Doing power-back with engine mounted aircraft has caused airplane damage, injuries, and crashes.
The turboprops that everyone is talking about can, but it is rare that they do this. Most of the times, they prefer to have someone else push them back. The speed at which they reverse is considerably slow and not worth the extra fuel. Working on the ramp for a regional airline, I only saw this once or twice.
So the short answer is, yes and a few rare instances no.
2006-06-17 22:27:09
·
answer #2
·
answered by mntennis_stud 2
·
0⤊
0⤋
No! Aircrafts cannot move back. They only move forward---either by their own engine thrust or by Towing with a specially designed tractor (this tractor has a drive rod which is connected to the nose wheel of the aircraft to tow it as desired).
It will take time when we will have aircrafts which can move 'forward' and 'backward' like cars!
Some more points on why backward movement is not possible:
1. Reverse Thrusters: (Most people misunderstand 'Reverse Thrusters' as 'something' which makes the propeller to rotate 'Clockwise' if they were rotating 'Counterclockwise' or vice-versa. This is technically 'impossible'---currently. So much stress is generated when you are turning the blades in one diretion that reversing them means creating so much vibration that the aircraft will disintegrate. An aircraft is designed to withstand a maximum of 6G scale of acceleration. It will break beyond this.). Reverse Thrusters are arrangements which 'minimize' the effect of forward thrust (propusion) by 'redirecting' or 'bypassing' it. An engine which can thrust both 'forward' or 'backward' would require very complex blades.
2. Rear View Mirror: An aircraft doesn't have a rear view mirror as in a car. A pilot will have difficulty in moving back---like moving in dark.
3. Nose Wheel: Only nose wheel gives direction. The middle wheels are subject to differential braking. That is when you have to turn right, you have to apply brakes on the right middle wheels and keep turning the left middle wheels (turning means thrust from the engine) and vice versa, while turning the nose-wheel at the same time (you do it by a dial type knob---as in a radio transistor---holding it in CW or CCW direction). So, you would require another set of 'Tail Wheel' (like 'Nose Wheel') to give it backward direction!
So, you can see, an aircraft cannot move backwards! ONLY FORWARD. I can imagine, days are not far when you would want to fly 'backwards' to the same airport by turning the propellers reverse! Great!
2006-06-17 18:31:24
·
answer #3
·
answered by Ask Dr. Dingo 3
·
0⤊
0⤋
The C-17, (the USAF's newest cargo airlifter) can reverse UPHILL! As many people have already written, this is done by redirecting the thrust from the engine forward. The engines are wing mounted but since it is a high wing aircraft, the engine are sufficiently high off the ground. Believe it or not thrust reversers are also sometimes actually deployed in flight to facilitate fast descents.
2006-06-18 09:02:20
·
answer #4
·
answered by zmonte 3
·
0⤊
0⤋
let's clarify this a bit : NO & YES ! everyone is right & everyone is wrong , lol
Seriously, a lot of prop driven planes can move slowly in reverse by changing the pitch of their propeller blades.Not all prop planes can do this, they need to be equipped to do so . The large C-130 can short-stop and then back up to take off again without ever turning around.
Jets have thrusters which can reverse them slowly, although they are used primarily for braking.so , if you are talking about a large jet , no, they need something to taxi them if they miss their mark.
2006-06-17 12:38:04
·
answer #5
·
answered by frith25 4
·
0⤊
0⤋
"Reverse Thrusters" are something from Star Trek, not present day planet Earth. lol However, jets DO have "thrust reversers", which are usually air ducts that direct the outflow of the jet engines forward, to slow the jet upon touchdown, or to back the jet up if no pushback tractor is available. I have seen jets back away from the terminal using only their thrust reversers.
Frith25's answer is correct about the C-130. Gergely's is also correct.
2006-06-18 06:49:23
·
answer #6
·
answered by Sky K 2
·
0⤊
0⤋
Getting out from a jet using a parachute is hard even for those well experienced personel from the arms. High skills are needed to do that. The speed is the biggest matter against you and the doors aren´t designed to open during the flight. Even when a person get on a plane with the intension of sky diving, is hard to jump out. Can you imagine what can hapen in a emergency situation?
2016-05-19 23:02:49
·
answer #7
·
answered by Anonymous
·
0⤊
0⤋
NO!!! Since planes don't have gears like cars and you can't put them in reverse. It is impossible for them to back up. They would need to install the plane's engines backwords to make them revers. Not possible on passenger planes or any other kind. They are made to fly not back up. Backing up is not such an important part of their job. NO NO NO.
2006-06-17 10:50:05
·
answer #8
·
answered by JOE 4
·
0⤊
0⤋
Yes, they can; this is called 'power-back' (unlike 'push-back' when they are towed). Turboprop and rear-mounted engine jet planes can use power-back (jets with engines on wings don't as there would be a danger of ingestion). It is a common sight on US airports in peak times.
See a video of a power-back here:
http://www.flightlevel350.com/viewer.php?id=1973
2006-06-17 20:55:52
·
answer #9
·
answered by Gergely 5
·
0⤊
0⤋
Joe Black is incorrect. I have been on multiple different types of aircraft that do this. Also, it's a standard airshow routine for the C-130 to do it. You could probably find a video online somewhere.
2006-06-17 11:42:24
·
answer #10
·
answered by Anonymous
·
0⤊
0⤋