8
$\begingroup$

In my company on the older A320s particularly the ones which are in the MSN 2000 range their tailwind limitation for takeoff and landing is 10 knots. But our newer enhanced ones have a 15 knots limitation. Any reason for this? Does Airbus do any modifications to the aircraft so that it's tailwind limit increases?

$\endgroup$
  • $\begingroup$ I believe it may be customer specific. In my old company, it seemed possible to purchase increased tailwind limits from the OEM for some aircraft types. Not sure whether that is the case for old A320s, though. $\endgroup$ – Cpt Reynolds Jan 27 '18 at 20:53
  • $\begingroup$ At least three possible reasons come to mind, a) more powerful engines, b) better breaking - perhaps improved carbon brakes. c) better electronics to handle rejected takeoffs. Also improved mechanisms such as speed brakes or lift dumpers. - this is just a guess that perhaps will help someone else in their research :) $\endgroup$ – jwzumwalt Jan 28 '18 at 10:17
  • $\begingroup$ @jwzumwalt Do you mean "braking"? $\endgroup$ – dalearn Jan 28 '18 at 15:42
3
$\begingroup$

Short answer: the increase from 10 to 15 knots requires extra certification / flight testing, which is an extra item the airline will pay for.


Over at pprune:

Boeing offers an increased tailwind limit of up to 15 knots for a fee.

I suspected that but had no proof, so that got the ball rolling.

From page 35 of an Airbus presentation presented to the civil aviation authority of PRC confirmed that being an option:

Other configurations outside China include options as:

  • Water/waste freezing protection for extended flight conditions
  • 15 knots tailwind certification at landing
  • 15 knots tailwind certification at take off

And finally from the FAA's Flight Test Guide For Certification Of Transport Category Airplanes, there is a section for certifying takeoff and landing in tailwind greater than 10 knots.

It requires the demonstration of controllability, engine performance, autoflight systems, landing gear vibration, terrain awareness warning systems to not be affected by the higher sink-rank, etc.

Note that for a takeoff in tailwind >10 knots, even the application of takeoff thrust is different from when <10 knots. The advisory circular also calls for a disclaimer of sorts to be added in the AFM:

The AFM should contain a statement that the limitation for tailwinds greater than 10 knots reflects the capability of the airplane as evaluated in terms of airworthiness but does not constitute approval for operation in tailwinds exceeding 10 knots.

Of course if the airline would also pay even more for the brake cooling fans option, they can reduce the longer cool down period after a tailwind landing, for example.


Some performance enhancements require extra certification and testing, but not necessarily extra equipment.

An airline can request their fleet to be certified for a lighter or higher MTOW depending on their operation. A light MTOW on the certification is cheaper to obtain, and it will allow the airline to save on ramp fees, route charges, etc. But on the other hand they can't carry as much payload/fuel. Other high MTOW options may require extra strengthening built into the airframe and more powerful engines.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.