# Why can't a Harrier do Pugachev's Cobra? **URL:** \ **Category:** Factual Questions\ **Created:** [January 30, 2014, 12:21am UTC](https://boards.straightdope.com/t/why-cant-a-harrier-do-pugachevs-cobra/680089 "2014-01-30T00:21:46Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Habeed](https://avatars.discourse-cdn.com/v4/letter/h/a587f6/32.png) [@Habeed](https://boards.straightdope.com/u/Habeed)\ **Post date:** [January 30, 2014, 12:21am UTC](https://boards.straightdope.com/t/why-cant-a-harrier-do-pugachevs-cobra/680089/1 "2014-01-30T00:21:46Z")
Pugachev’s Cobra is an aerobatic maneuver used to sell aircraft. It involves pitching the nose up in a maneuver that stalls the flight controls. Wikipedia says that in order to perform it, the aircraft needs thrust vectoring or a reaction control system and a thrust/weight ratio \> 1. A harrier can hover, so it must have a TWR \> 1, and it has a reaction control system. Why can it not perform the maneuver? Does the reaction control system not work when the engine is in the rearward facing position? ---
**Author:** ![Amateur\_Barbarian](https://avatars.discourse-cdn.com/v4/letter/a/59ef9b/32.png) [@Amateur\_Barbarian](https://boards.straightdope.com/u/Amateur_Barbarian)\ **Post date:** [January 30, 2014, 1:03am UTC](https://boards.straightdope.com/t/why-cant-a-harrier-do-pugachevs-cobra/680089/2 "2014-01-30T01:03:45Z")
The Cobra is performed entirely by balancing a full stall on top of extraordinary thrust. I think a Harrier just can’t pull off that combination of stall stability and rear thrust; using the RCS is too slow and clumsy for such a delicate maneuver. Maybe a Russian Harrier pilot will chime in to correct us. 😃 ETA: I just looked at some YouTube clips - I thought a full Cobra involved a 180 along with the dramatic pull-up - sort of a supersonic-era Immelman. Is it only an extreme braking maneuver designed to stall back on a pursuer? ---
**Author:** ![LawMonkey](https://avatars.discourse-cdn.com/v4/letter/l/d6d6ee/32.png) [@LawMonkey](https://boards.straightdope.com/u/LawMonkey)\ **Post date:** [January 30, 2014, 1:08am UTC](https://boards.straightdope.com/t/why-cant-a-harrier-do-pugachevs-cobra/680089/3 "2014-01-30T01:08:29Z")
Why are you certain that it can’t? I don’t necessarily see anything to that effect on the wikipedia page or searching for the term “pugachev’s cobra harrier” on google. In fact, the latter actually gets me a hit on the Pugachev’s cobra wiki talk page where it sounds like someone is discussing a harrier having done it (or something similar) in the Falklands war. ---
**Author:** ![Amateur\_Barbarian](https://avatars.discourse-cdn.com/v4/letter/a/59ef9b/32.png) [@Amateur\_Barbarian](https://boards.straightdope.com/u/Amateur_Barbarian)\ **Post date:** [January 30, 2014, 1:14am UTC](https://boards.straightdope.com/t/why-cant-a-harrier-do-pugachevs-cobra/680089/4 "2014-01-30T01:14:57Z")
> [@LawMonkey](#): > > Why are you certain that it can’t? It’s certainly not authoritative, but I found a number of mentions that the F-22 is the only non-Soviet/Russian bird that can do it. Seems that if the Harrier could do it or ever had done it, legions would pop up to argue that claim. In fact, I think only three planes can do it - Mig-29, Su-27 and F-22. Any others? ---
**Author:** ![LawMonkey](https://avatars.discourse-cdn.com/v4/letter/l/d6d6ee/32.png) [@LawMonkey](https://boards.straightdope.com/u/LawMonkey)\ **Post date:** [January 30, 2014, 1:24am UTC](https://boards.straightdope.com/t/why-cant-a-harrier-do-pugachevs-cobra/680089/5 "2014-01-30T01:24:28Z")
Again, just citing the [Wikipedia page](http://en.wikipedia.org/wiki/Pugachev%27s_Cobra), but even dropping the “citation needed” planes (the F-15 STOL/MTD, F-16 and Su-47), we’ve got the J-10, the F-22, the PAK-FA, and the Saab 35 Draken. I would not be in the least surprised if there’s not some aerospace engineer on the Dope waiting to explain this all to us. 🙂 ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [January 30, 2014, 3:29am UTC](https://boards.straightdope.com/t/why-cant-a-harrier-do-pugachevs-cobra/680089/6 "2014-01-30T03:29:53Z")
> [@LawMonkey](#): > > Why are you certain that it can’t? I don’t necessarily see anything to that effect on the wikipedia page or searching for the term “pugachev’s cobra harrier” on google. In fact, the latter actually gets me a hit on the Pugachev’s cobra wiki talk page where it sounds like someone is discussing a harrier having done it (or something similar) in the Falklands war. I think what the British pilot did in the Falklands was basically vector his thrust forward (or close to it), decelerating extremely fast, and the Argentinian plane shot right by. ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [January 30, 2014, 10:00am UTC](https://boards.straightdope.com/t/why-cant-a-harrier-do-pugachevs-cobra/680089/7 "2014-01-30T10:00:35Z")
That is exactly it. > **[Thrust vectoring](https://en.wikipedia.org/wiki/Vectoring_in_forward_flight)** > > Thrust vectoring, also known as thrust vector control (TVC), is the ability of an aircraft, rocket, or other vehicle to manipulate the direction of the thrust from its engine(s) or motor(s) to control the attitude or angular velocity of the vehicle. > In rocketry and ballistic missiles that fly outside the atmosphere, aerodynamic control surfaces are ineffective, so thrust vectoring is the primary means of attitude control. Exhaust vanes and gimbaled engines were used in the 1930s by Robert > God... ---
**Author:** ![LawMonkey](https://avatars.discourse-cdn.com/v4/letter/l/d6d6ee/32.png) [@LawMonkey](https://boards.straightdope.com/u/LawMonkey)\ **Post date:** [January 30, 2014, 2:21pm UTC](https://boards.straightdope.com/t/why-cant-a-harrier-do-pugachevs-cobra/680089/8 "2014-01-30T14:21:46Z")
Ahhh. Cool maneuver, bro. 🙂 ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [January 30, 2014, 7:13pm UTC](https://boards.straightdope.com/t/why-cant-a-harrier-do-pugachevs-cobra/680089/9 "2014-01-30T19:13:45Z")
> [@Amateur\_Barbarian](#): > > Is it only an extreme braking maneuver designed to stall back on a pursuer? The Soviets actually developed the maneuver as a way to break radar lock. It otherwise isn’t a terribly useful maneuver for air combat. It leaves you nearly stationary (which is the part that screws up tracking radar) with your weapons and the pilot’s field of view both pointed uselessly upward. All of the plane’s speed and energy is lost during the maneuver, and the recovery back to controlled flight takes several seconds, during which defensive maneuvering is extremely limited due to the plane’s lack of speed. It’s also a very impressive maneuver that sells airplanes, as the OP noted. Even though its use is fairly limited, it caused quite a stir in the late 80’s and early 90’s when the Soviets first showed it off at air shows.