G STRV-banner%20-%20small

Mechanical Stall Warning??

IMG 0047

Vans have supplied the kit with two pilot holes ready for the Stall Warner Vane slot.

I have asked the LAA (Light Aircraft Association, UK) whether I will be compelled to fit a mechanical stall warner, since I plan to fit a pitot probe with AOA. This will of course be displayed on an EFIS with audio warning.

I suspect I’ll need to apply for an official modification, but in the meantime I’ve decided not to cut the slot. Instead I’ve machine countersunk the holes & fitted small OOP’s rivets.

If it turns out that I have to fit a stall warning vane after all, I’ll drill out the rivets and open up the holes to #10 as per the manual, and file the slot. Apparently there are several RV7’s & 8’s in the UK flying with no mechanical stall warner, so it bodes well, but fingers crossed

Information for UK builders: The LAA have now agreed that a correctly configured AOA stall warning when displayed on an EFIS with aural warning is acceptable.

28 June 2023

I’ve prepared the brackets that attach the stall warning microswitch, and will also rivet the relevant nutplates to the left inboard LE rib just in case it has to be incorporated.

IMG 0059

5 comments on Mechanical Stall Warning??
  1. Bill Sweetnam

    Hi Steve… great blog!
    I’m on the home straight with my 14 QB tail dragger…full G3x ifr installation…
    Also wondering about the mechanical stall warner…did you ever get a ruling on this? Otherwise I’ll just leave wires in place and be able to fit later.

    1. Steve

      Hi Bill … thanks for your comment. I contacted the LAA who said the following … “In summary, yes, we’d be happy for you to use the Garmin AoA system in lieu of a mechanical stall warning device, subject to the test pilot confirming that it gives an appropriate/obvious warning of an impending stall and the visual component of the warning is also sufficiently clear.” They said they are planning to publish a Technical Leaflet about this topic, but I haven’t seen anything yet. I’ve sent you a private email with a little more info.

  2. Mark Browning

    Hi Bill
    I’m building a 14 in Doncaster
    I’m planning my avionics and did not fit a stall Warner
    When I built the wings with the intention of using the AOA
    And Garmin 3GX
    Would it be possible for you to forward any details or confirmation on this please
    I really need to nail this down before I paint the wings
    Many thanks

  3. Steve

    Hi Mark … I’ve heard nothing different from the LAA than my original reply to Bill last June (see above). Just sent you an email.

    1. Mark Browning

      Thanks Steve

      Our RV-7 has Dynon D100 with AOA and no stall Warner
      To be honest I’ve flown all the RV’s and there’s no problem with stall , they give you lent of warning although the 8 is a little more slippery.
      It could be our aircraft engineer never picked It up, unfortunately He recently passed away. We have being flying this for ten years.
      I have to get to confirmation on this from LAA or my engineer
      Before I paint later this year
      Thanks for all your help 👍
      Best regards

Leave a Reply

Your email address will not be published. Required fields are marked *