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It is a well known fact that some planes like the Antonov An-2 can fly backwards since their stall speed is lower than the speed of the winds they can stably fly into. My question is what is the fastest recorded backward flying plane and is there video of this phenomenon?

In response to the comments by @Simon et al the term backwards was vague - backwards relative to the ground would have been more accurate.

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    $\begingroup$ OK, I'll be the pedant. The An-2 cannot fly backwards, nor can any other conventional aircraft. If the wind is fast enough, you might have a negative ground speed but you are still flying forwards. $\endgroup$ – Simon Jun 16 '15 at 8:06
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    $\begingroup$ I'd suggest gliders is one possible source for info - especially people using mountain wave lift for altitude flights. Station keeping in strong high-altitude winds is fairly common in that style of flying. $\endgroup$ – Andy Jun 16 '15 at 11:51
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    $\begingroup$ I think Simon meant "negative ground speed" to mean the same thing as velocity with respect to the wind direction. Is further definition of common words necessary? $\endgroup$ – Andy Jun 16 '15 at 13:59
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    $\begingroup$ @V-J I'm perfectly aware of the science of flight, the difference between a scalar and a vector and the definitions of common words thank you. A conventional aircraft can only fly if the relative airflow velocity is positive with respect to the aircraft frame of reference and it's lift generation devices. Therefore, when flying, it's speed is always positive (as will be shown by the airspeed indicator). It is not possible to fly backwards. $\endgroup$ – Simon Jun 16 '15 at 15:01
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    $\begingroup$ @V-J And I had a big smile when I wrote it ;) I won't post an answer since I am being cheeky, a pedant and a smart a**. I understand what the OP means and will leave it to others to answer. I don't have a good contribution. Cheers. $\endgroup$ – Simon Jun 16 '15 at 18:16
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The only true answer I'm aware of is the Hawker Harrier (or Harrier derivatives thereof) which can fly at ~650mph and can also truly fly backwards - ie it can literally fly backwards, in still air or against a light tailwind.

I would assume that the Boeing V-22 Osprey and F-35C are capable of a similar feat, but have no evidence of this to hand.

As to your original question, the answer is that any aircraft is capable of this feat of "moving in reverse relative to the ground", if the wind speed is higher than that aircraft's stall speed.

I'm not quite sure what your question is, as you ask what is the fastest plane which can do this: Do you mean "What is the maximum speed of any aircraft which can achieve this?" or did you mean "How high can this relative speed be"

For the former: With the maximum wind speed recorded on Earth being over 230mph, any aircraft with a stall speed of 230mph or lower (ie, almost any plane), can do it. Therefore the fastest aircraft which can achieve this is the fastest aircraft on the planet. I'm not 100% sure on the fastest aircraft, but the SR-71, for example, can fly at well over Mach 3, but is also capable of flying "backwards" if the wind speed is above around 180 knots.

In theory the SR-71 could therefore fly at Mach 3 "forwards" or around 50mph "backwards" (in the context of this question) by travelling at 180 knots into a 230mph headwind. I wouldn't recommend attempting this, however....

Or to answer the real question I think you're asking which is "How fast can an aircraft performing this feat travel relative to the ground", the answer would be "the aircraft with the slowest possible stall speed" and the relative speed would be approximately 200mph.

An aircraft which can fly at under 30 knots, flying into that 230mph headwind, would be travelling "backwards" at 200mph relative to the ground, and at 30 knots relative to the wind.

So actually with it's very low stall speed the An-2 is probably a contender, although I believe there are aircraft with lower stall speeds.

(Apologies for mixing Knots and MPH almost at random in this reply: all numbers are approximate, however, so it probably doesn't matter too much. For the purposes of this answer, I'm treating 1 kt and 1 mph as approximately equal)

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    $\begingroup$ In the "for what its worth department": A US Marine aircraft mechanic told me the Harrier can fly 120 knots backwards. $\endgroup$ – radarbob Sep 1 '15 at 21:41
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    $\begingroup$ I think you mean the F35B, which is the STOVL variant. $\endgroup$ – Liam Baron Sep 2 '15 at 8:24

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