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Re: Planes take off , off trailer
[Re: FM3AAR]
#2794834
07/09/20 05:01 PM
07/09/20 05:01 PM
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Joined: Aug 2019
Posts: 9,456
Super Spudsville
Mr PotatoHead
Half Baked
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Half Baked
Joined: Aug 2019
Posts: 9,456
Super Spudsville
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Dosent take a rocket scientist to know how they commonly get water/only planes airborn where there is no water at times, notice it was a runway it took off from.
STOP POTATO HATE!
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Re: Planes take off , off trailer
[Re: Mr PotatoHead]
#2794860
07/09/20 05:33 PM
07/09/20 05:33 PM
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Joined: Oct 2007
Posts: 3,884
Oregon
hooziewhatsit
master
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master
Joined: Oct 2007
Posts: 3,884
Oregon
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 Of course a plane can take off from a treadmill.  The original question was flawed in that it made the assumption that the treadmill could hold the plane and prevent forward motion. Put a wheelbarrow on a treadmill and observe that no matter how fast you make the treadmill go, you can still move the wheelbarrow forward and back just fine => a plane can take off from a treadmill too 
If you ever find yourself in a fair fight, your tactics suck.
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Re: Planes take off , off trailer
[Re: Mr PotatoHead]
#2794861
07/09/20 05:35 PM
07/09/20 05:35 PM
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Joined: May 2012
Posts: 1,821
South Bend
John Brown
top fuel
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top fuel
Joined: May 2012
Posts: 1,821
South Bend
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Take off speed is likely less than 50 mph, so not a great risk involved for the tow truck.
July 19th should be "Drive Like Rockford Day". R.I.P. Jimmie.
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Re: Planes take off , off trailer
[Re: hooziewhatsit]
#2794866
07/09/20 05:48 PM
07/09/20 05:48 PM
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Joined: Nov 2007
Posts: 21,823
Kirkland, Washington
Pacnorthcuda
Too Many Posts
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Too Many Posts
Joined: Nov 2007
Posts: 21,823
Kirkland, Washington
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Of course a plane can take off from a treadmill. The original question was flawed in that it made the assumption that the treadmill could hold the plane and prevent forward motion. Put a wheelbarrow on a treadmill and observe that no matter how fast you make the treadmill go, you can still move the wheelbarrow forward and back just fine => a plane can take off from a treadmill too A planes ability to take off is based on AIRSPEED. Air flowing over the wing creates LIFT. The airspeed can be from the planes forward motion, of from a headwind, or both, but it needs airspeed. Period.
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Re: Planes take off , off trailer
[Re: Pacnorthcuda]
#2794869
07/09/20 05:54 PM
07/09/20 05:54 PM
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Joined: Jan 2003
Posts: 9,117
Tucson, AZ
Ramrod39
My New Title
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My New Title
Joined: Jan 2003
Posts: 9,117
Tucson, AZ
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A planes ability to take off is based on AIRSPEED. Air flowing over the wing creates LIFT. The airspeed can be from the planes forward motion, of from a headwind, or both, but it needs airspeed. Period.
Yep. If the air is move over and under the wings at sufficient speed the plane can fly even if the plane is stationary.
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Re: Planes take off , off trailer
[Re: Pacnorthcuda]
#2794876
07/09/20 06:06 PM
07/09/20 06:06 PM
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Joined: Oct 2007
Posts: 3,884
Oregon
hooziewhatsit
master
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master
Joined: Oct 2007
Posts: 3,884
Oregon
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Of course a plane can take off from a treadmill. The original question was flawed in that it made the assumption that the treadmill could hold the plane and prevent forward motion. Put a wheelbarrow on a treadmill and observe that no matter how fast you make the treadmill go, you can still move the wheelbarrow forward and back just fine => a plane can take off from a treadmill too A planes ability to take off is based on AIRSPEED. Air flowing over the wing creates LIFT. The airspeed can be from the planes forward motion, of from a headwind, or both, but it needs airspeed. Period. Correct! And a treadmill is incapable of preventing a plane from making forward motion or the resulting airspeed, so it then takes off 
If you ever find yourself in a fair fight, your tactics suck.
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Re: Planes take off , off trailer
[Re: poorboy]
#2794966
07/09/20 10:02 PM
07/09/20 10:02 PM
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Joined: Aug 2003
Posts: 43,176
Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,176
Bend,OR USA
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I'll bet landing is more impressive then taking off. Exactly how do they land water planes at an airport? Gene Most float planes have retractable wheels in the floats and retractable rudders so they can lift the rudder to use the wheels to land on hard surfaces and lower the rudders and raise the wheels to land on water Same thing on the other type of planes,( amphibieans (SP?) that where designed primarily to land and take off on water, they have wheels in the floats to land and or taxi on hard surfaces when needed
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: Planes take off , off trailer
[Re: Mr PotatoHead]
#2795048
07/10/20 08:51 AM
07/10/20 08:51 AM
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Joined: Jun 2004
Posts: 3,380
St. Charles, MO
wingman
Uncreative Title
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Uncreative Title
Joined: Jun 2004
Posts: 3,380
St. Charles, MO
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But was the trailer on a treadmill?
1969 Dodge Coronet Super Bee 383 A4
1970 Plymouth Road Runner 440 FC7 (sold)
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Re: Planes take off , off trailer
[Re: wingman]
#2795085
07/10/20 10:11 AM
07/10/20 10:11 AM
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Joined: Nov 2003
Posts: 2,937
GA
roadrunninMark
master
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master
Joined: Nov 2003
Posts: 2,937
GA
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An airplane will not take off on a treadmill if it is maintaining its position. I will relate this to someone running on a treadmill for comparison sake, since almost everyone has been on a treadmill. If you stand on a treadmill, it will move you backwards. You have to run/walk to at exact the same speed in the opposite direction to maintain your position. If you do this, your upper body is in a stationary position. You do not gain nor lose ground. Step off the treadmill while you are maintaining this speed and you instantly go forward. Stop running/walking and you instantly go backward. There is no airflow around you, since you are in a stationary position. Remember when you were young and stuck your hand out the window of a moving vehicle? You made a “wing shape” with your hand? If you tilted your hand up, it would lift your hand/arm. Opposite if you tilted your hand down. Try this next time you are on a treadmill, no airflow over or under your hand. Without airflow, a plane will not fly.
If you think because the propellor is turning, creating airflow to fly, then just look at the above video. Why would the plane need a truck then to pull it down the runway before it would take off from the platform? Think of the platform being a treadmill and the floats being the legs. It is maintaining its position on the platform, no forward nor backward movement. Even with the propellor turning, the plane still needed a certain speed forward before it reached a speed it could takeoff.
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Re: Planes take off , off trailer
[Re: roadrunninMark]
#2795099
07/10/20 11:06 AM
07/10/20 11:06 AM
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Joined: Oct 2007
Posts: 3,884
Oregon
hooziewhatsit
master
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master
Joined: Oct 2007
Posts: 3,884
Oregon
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An airplane will not take off on a treadmill if it is maintaining its position. I will relate this to someone running on a treadmill for comparison sake, since almost everyone has been on a treadmill. If you stand on a treadmill, it will move you backwards. You have to run/walk to at exact the same speed in the opposite direction to maintain your position. If you do this, your upper body is in a stationary position. You do not gain nor lose ground. Step off the treadmill while you are maintaining this speed and you instantly go forward. Stop running/walking and you instantly go backward. There is no airflow around you, since you are in a stationary position. Remember when you were young and stuck your hand out the window of a moving vehicle? You made a “wing shape” with your hand? If you tilted your hand up, it would lift your hand/arm. Opposite if you tilted your hand down. Try this next time you are on a treadmill, no airflow over or under your hand. Without airflow, a plane will not fly.
If you think because the propellor is turning, creating airflow to fly, then just look at the above video. Why would the plane need a truck then to pull it down the runway before it would take off from the platform? Think of the platform being a treadmill and the floats being the legs. It is maintaining its position on the platform, no forward nor backward movement. Even with the propellor turning, the plane still needed a certain speed forward before it reached a speed it could takeoff. Not quite. In your treadmill example, the forward motion is coming from the person running pushing back on the treadmill. Go back up and look at my wheelbarrow on a treadmill example. It doesn't matter how fast the treadmill is going; you'll still be able to push the wheelbarrow forward on the moving treadmill. The treadmill is incapable of holding it back. Hence, the propeller creates forward motion and airspeed, and it takes off.
If you ever find yourself in a fair fight, your tactics suck.
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Re: Planes take off , off trailer
[Re: hooziewhatsit]
#2795118
07/10/20 12:19 PM
07/10/20 12:19 PM
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Joined: Jan 2005
Posts: 8,341
Crook County, ILL
Mastershake340
master
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master
Joined: Jan 2005
Posts: 8,341
Crook County, ILL
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In this case the plane isn't much different than a glider. A glider gets towed either by a powered aircraft or a winch/catapult type mechanism on the ground, and when the airflow over the wings is fast enough to create adequate lift, the glider flies. Or maybe better to compare to a plane getting catapulted off an aircraft carrier, where the catapult accelerates the plane to a speed where the wings develops lift, and then the thrust of the engines takes over to keep the plane flying at a speed required to maintain the lift. If you put an airplane with the engine not running on a platform and accelerated the platform fast enough, the plane would start to fly after developing lift, and the plane would glide back down to the ground, or stall and crash into the ground depending on circumstances and how fast the pilot could react on the controls etc. I thought the old plane on a treadmill theory had got beaten to death years ago, even Mythbusters did an episode on that. 
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Re: Planes take off , off trailer
[Re: John_Kunkel]
#2795201
07/10/20 03:44 PM
07/10/20 03:44 PM
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Joined: Feb 2003
Posts: 8,671
Andrewh
master
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master
Joined: Feb 2003
Posts: 8,671
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Re: Planes take off , off trailer
[Re: Andrewh]
#2795253
07/10/20 06:46 PM
07/10/20 06:46 PM
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Joined: Nov 2003
Posts: 2,937
GA
roadrunninMark
master
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master
Joined: Nov 2003
Posts: 2,937
GA
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Sorry, but no Hoosie. The treadmill is causing you to go backwards. Therefore, you have airflow coming from behind you if you are losing ground. You are moving forward against the belt, yes, but not the relative wind. You will not takeoff, you will not fly, and you will not collect 200 bux (you will not pass go!) LOL
The only way you can takeoff on a treadmill is if you have a very loooooooooooooooooong treadmill and you are actually moving forward on it. AND the problem with this is that the engine will have to spin even faster to offset the original speed of the treadmill. Now if the treadmill is running in reverse, you will need less power, just like the truck pulling that float plane!
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Re: Planes take off , off trailer
[Re: roadrunninMark]
#2795256
07/10/20 07:06 PM
07/10/20 07:06 PM
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Joined: Jun 2004
Posts: 3,380
St. Charles, MO
wingman
Uncreative Title
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Uncreative Title
Joined: Jun 2004
Posts: 3,380
St. Charles, MO
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Wow. I can't believe we are having this conversation again!  I think some car guys have trouble grasping the concept because they are so used to thinking about wheels pushing against the pavement. In a plane the engine is pushing against the air, not the ground. So a conveyor belt has no effect other than to make the landing gear wheels spin a little faster. No effect.
1969 Dodge Coronet Super Bee 383 A4
1970 Plymouth Road Runner 440 FC7 (sold)
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Re: Planes take off , off trailer
[Re: roadrunninMark]
#2795257
07/10/20 07:11 PM
07/10/20 07:11 PM
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Joined: Oct 2007
Posts: 3,884
Oregon
hooziewhatsit
master
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master
Joined: Oct 2007
Posts: 3,884
Oregon
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Nope.
Stand on the ground, holding a wheelbarrow, and put the front wheel on a treadmill. Speed up the treadmill, and observe how the wheel spins at the same speed as the treadmill, but the wheelbarrow stays in one place.
Then see that if you push the wheelbarrow forward (on the moving treadmill), it moves forward regardless of how fast the treadmill is going. Heck, make the treadmill go in reverse, and observe how you can still push the wheelbarrow forward and back.
The original question is flawed in assuming the treadmill can hold the plane back. It can't.
HOWEVER, if the wheels of the plane were driven by the engine to be the same speed as the treadmill, then yes, it would never have any forward motion or airspeed, and never take off. But I've never seen a plane with powered wheels.
If you ever find yourself in a fair fight, your tactics suck.
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Re: Planes take off , off trailer
[Re: wingman]
#2795259
07/10/20 07:12 PM
07/10/20 07:12 PM
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Joined: Oct 2007
Posts: 3,884
Oregon
hooziewhatsit
master
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master
Joined: Oct 2007
Posts: 3,884
Oregon
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Wow. I can't believe we are having this conversation again! I think some car guys have trouble grasping the concept because they are so used to thinking about wheels pushing against the pavement. In a plane the engine is pushing against the air, not the ground. So a conveyor belt has no effect other than to make the landing gear wheels spin a little faster. No effect.
If you ever find yourself in a fair fight, your tactics suck.
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Re: Planes take off , off trailer
[Re: Ramrod39]
#2795299
07/10/20 09:20 PM
07/10/20 09:20 PM
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Joined: Nov 2003
Posts: 2,937
GA
roadrunninMark
master
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master
Joined: Nov 2003
Posts: 2,937
GA
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Hoosie, your example is flawed. If someone stands on the ground holding the handles of the wheelbarrow, of course the wheel will speed up or slow down with the speed of the treadmill, but it is only the wheel. The person is acting as an anchor. Again, the body of the wheelbarrow is not moving forward or reverse. Also, how does this even relate to an airplane if it was on the treadmill? Is there a wheel (tail or nose wheel, doesn't matter which) that will not be on the treadmill? If this is the case, again, the wheels will spin but the airplane will have no forward momentum, as the person. Therefore, no airflow over the wings of the relative wind (only the wind blown by the propeller, which is no where near enough airflow).
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Re: Planes take off , off trailer
[Re: Andrewh]
#2795339
07/11/20 12:54 AM
07/11/20 12:54 AM
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Joined: Oct 2007
Posts: 3,884
Oregon
hooziewhatsit
master
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master
Joined: Oct 2007
Posts: 3,884
Oregon
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Andrew is correct. Instead of hanging on to the wheelbarrow, put an engine with a propeller in it. And assume it balances on one wheel. It's an analogy, deal with it The propeller will provide the forward motion, just like when you push it by hand.
If you ever find yourself in a fair fight, your tactics suck.
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Re: Planes take off , off trailer
[Re: hooziewhatsit]
#2795437
07/11/20 12:14 PM
07/11/20 12:14 PM
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Joined: Nov 2003
Posts: 2,937
GA
roadrunninMark
master
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master
Joined: Nov 2003
Posts: 2,937
GA
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I know the aircraft doesn't depend on wheel speed to be able to takeoff,and I said that earlier, it depends upon the relative wind moving, mainly under the wing surface. I was referencing Hoosie's statement of one holding the end of the wheelbarrow with the treadmill rotating the wheel.
Now in his new example, he is putting a propeller and engine on the wheelbarrow. On one wheel, 3 wheels, doesn't matter how many wheels, the propeller now pulling wheelbarrow/airplane forward, yes the engine, if strong enough, can counteract the treadmill as it attempts to move the wheelbarrow/airplane backwards. If WB/AP is in a static position, (treadmill moving it back at same speed engine pulling it forward) it will NOT take off. IF the engine is pulling it forward, at a speed it would normally lift off at (in this case: Takeoff speed = normal rotation speed (at a given weight) + speed to overcome the treadmill's belt speed, then yes it is possible.
So if you have a treadmill that is EXTREMELY long, and the aircraft is actually making forward progress and is able to overcome the treadmill speed AND reach normal takeoff speed, then yes it is possible. If it cannot read that speed, then no, it isn't going to takeoff.
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Re: Planes take off , off trailer
[Re: roadrunninMark]
#2795448
07/11/20 12:52 PM
07/11/20 12:52 PM
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Joined: Jan 2003
Posts: 8,027
Tulsa OK
Bad340fish
master
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master
Joined: Jan 2003
Posts: 8,027
Tulsa OK
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So those of you who think a plan can't take off on a treadmill.......can a plane fly over a treadmill or will it fall from the sky? Could we pull aircraft from the sky with giant treadmills on the ground?
Planes aren't wheel driven, that is why they can take off on treadmills, a plane on a treadmill will still go forward with the thrust from the propeller, the wheels might be turning at a higher rate of speed than normal but it will take off just fine.
68 Barracuda Formula S 340
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Re: Planes take off , off trailer
[Re: 360view]
#2795818
07/12/20 01:47 PM
07/12/20 01:47 PM
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Joined: Oct 2007
Posts: 3,884
Oregon
hooziewhatsit
master
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master
Joined: Oct 2007
Posts: 3,884
Oregon
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My point with the wheelbarrow is to try and show how what the treadmill does has no effect on whether the plane can move forward or not, when acted on by the propeller.
Yea, a plane on a treadmill without the engine running will move backwards, but only until the engine starts. Then it will move forward like it was on solid ground.
If you ever find yourself in a fair fight, your tactics suck.
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