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I have been told that tail strikes on take off and landing are rare but do occur. I think, in my mind, the tail touching the ground at all would just make the tail fall off, but it appears I was wrong. In most of cases of tail strikes I've read about the plane is able to either continue on it's journey or can simply circle back to the field it departed from.

So I'm wondering, what do big commercial aircraft manufacturers (like Boeing and Airbus) do to keep tail strikes from turning into a major disaster? How do they engineer the plane to survive the incident?

Jae Carr
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    Do you have a source that supports tail strikes being common? I would characterize them as quite rare. – casey May 10 '15 at 02:07
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    @casey I actually really struggled with the wording for that part. All I'm trying to say is that it happens more often than "never", and it doesn't always involve major damage the the aircraft in common... In the end though I decided to just leave it because it's not really a part of the question, it's just a set up. But if you have any ideas on clarifying it... – Jae Carr May 10 '15 at 03:14
  • There are a number of hull types for planes. They include: truss, geodesic, monocoque, and semi-monocoque. Basically what you're asking is "Why don't tail strikes destroy the hull of a plane?" The answer is that each of these hull types provides some resistance to that type of blunt force. I don't have any actual sources to cite, but I would guess that the order of "most tolerance" for tail strikes would probably be: semi-monocoque, geodesic, monocoque, and then truss. However, that's just an educated guess based on their general designs. – Calphool May 10 '15 at 03:24
  • @Calphool That is at least the start of an answer though. I do know they also specifically engineer the tail section to deal with the force of a tail strike, sometimes adding skid plates or even a small wheel... But I've got scant details, so I'm hoping someone can step in and offer a more complete answer. – Jae Carr May 10 '15 at 04:03
  • I've watched thousands of takeoffs and landings and only ever seen 1 tailstrike. And that one was during an airshow when an F-15 pilot decided to do something spectacular and pulled up way too early on takeoff. He hit his tailpipes (both of them) on the asphalt, damaging his aircraft severely (I think he damaged the runway as well). So no, they're not at all common. – jwenting May 10 '15 at 04:41
  • @jwenting Again, it is a problem of wording, not my understanding. If you have a useful edit, please feel free. – Jae Carr May 10 '15 at 04:44
  • AFAIK, tailstrikes normally mean the plane needs repairs. It can't just take it without damage. JAL123 was ultimately caused by tailstrike damage (the repair perfomred was performed badly, but the basic issue was a crack caused by the tailstrike). – cpast May 10 '15 at 04:44
  • @jwenting There, I think that wording is better. I found an article on the WSJ that makes it sound like they happen at a rate of roughly once per year... Having a devil of a time finding hard numbers though: http://247wallst.com/special-report/2013/04/24/the-nine-most-common-airplane-accidents/ – Jae Carr May 10 '15 at 04:53
  • Though I did just find another article that says tail strikes happen at least 3 times a year to German aircraft (according the German investigators...). >< I don't like this lack of hard data... http://www.flyertalk.com/the-gate/blog/18769-the-tale-of-the-tail-strike-damaged-aircraft-crosses-ocean-—-and-no-one-realized-it.html – Jae Carr May 10 '15 at 04:56
  • But the overall point is that they happen, and I wonder how the damage is kept to a minimum. – Jae Carr May 10 '15 at 04:56
  • Sometimes the damage is severe...http://www.youtube.com/watch?v=C74ZXW2NlSY&search=airplanes – Skip Miller Jun 03 '15 at 00:39
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    I think the main engineering solution is that the bottom of the tail is curved inwards. If the under side is flat like in smaller aircrafts, tail strike would be a lot more common. Testing then verifies that the parameters used to calculate the rotation speed at take off gives sufficient vertical speed per rotation to avoid tail strikes. If this speed can't be achieved given the targeted runways length, then it's back to square one, adding more engine power, bigger wheels, more curve, wing designs to improve lifts, or by reducing the maximum rotation during take off. Engineering is iterative. – Lie Ryan Jun 03 '15 at 01:48
  • "the tail touching the ground at all would just make the tail fall off..." What, like the ship incident where the front fell off? – cjs Mar 25 '22 at 05:49

3 Answers3

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During testing, the rear fuselage is protected by a beam made of oak or even steel to distribute the tail strike loads and to protect the aircraft skin. A340 during tail strike tests A340 during tail strike tests. This one is literally blazing along the runway …

For normal operations, the protection is removed. However, tail strikes must not cause flight-critical damage, so a few precautions are taken during design:

  • No hydraulic or electrical lines must run along the bottom of the rear fuselage.
  • If there are still mechanical control elements like pushrods, they and their collapsing supports must not be close to the bottom of the fuselage.
  • The tail strike location must be outside of the pressurized part of the fuselage.

The main protection against tail strikes, however, is procedural: The rotation speed must be high enough to allow lift-off before a critical pitch attitude is reached.

Delta wing aircraft are much easier to over-rotate, so the Concorde used a retractable tailwheel for tail strike protection: BA Concorde tail from below with rear wheel extended

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Peter Kämpf
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The 777-300ER locks the gear bogey in the horizontal position during takeoff making it considerably more difficult to tailstrike (Boeing said they hit the ground 12 times during testing with the -300, but only got within 18 inches on the -300ER).

enter image description here Source

See these documents: 1, 2

Thunderstrike
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Firstly, this article from Boeing explains how tail strikes occur.

And this Boeing informational note gives more practical information on tail strikes and prevention:

A short excerpt from that note: "...some 777 models incorporate a tail strike protection system that uses a combination of software and hardware to protect the airplane. And some models of the 737, 767, and 777 have a tail skid that prevents damage from most takeoff tail strikes. However, these devices do not guarantee protection for landing tail strikes and some takeoff tail strikes. They also reduce tail clearance distances."

Gürkan Çetin
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