Thrush Aircraft, Inc. was formed in 2003 and has worked hard to continue to produce quality agricultural aircraft in the fine tradition that began in 1965 by North American Rockwell and later the Ayres Corporation.  As you continue to produce quality products, you learn ways to improve them as new technologies become available, field experience demonstrates a different way to do things, or the engineering department discovers ways to extend the service life of our aircraft – or even a particular part. Here at Thrush it’s usually a combination of all three that allows us from time to time to offer updates to our airframes – updates that are not mandatory, but that are designed to help you get even more productivity from your aircraft investment.

Here’s a listing of updates currently available. To learn more, please contact our Vice President Product Support & Development, Jody Bays, at (229) 789-0439 or This e-mail address is being protected from spambots. You need JavaScript enabled to view it. and he will be glad to talk through any updates as well as their application and installation.

Solutions to address Wing AD 2009-26-11 (This AD applies only to aircraft manufactured by the Ayres Corporation, built in 2000 or earlier).

(This AD applies only to aircraft manufactured by the Ayres Corporation, built in 1998 or earlier).

Even though this directive applies to aircraft built by the Ayres Corporation some 13 years ago, we are supporting operators by offering three different solution options.

1. You may purchase lower spar caps, which are available in pairs and include two lower 4340 Chrome-Molly steel spar caps with a safe life limit of 5,400 hours.
2. You may purchase our CK-AG-41 Spar Cap Modification Kit which includes:
   • Lower spar caps with first two splice block holes cold expanded
   • New inboard webs and doublers
   • 3/8” thick “Big Butterfly”
   • Lower splice plate
   The CK-AG-41 kit installation has been successfully tested to the fail-safe requirement of FAR [a][2] for a gross weight of 10,500 lbs and then tested to failure at a load of 19,111 lbs. That’s 13% more than the requirement! CK-AG-41 gathers all the previous service publications issued by the Ayres Corporation into a single kit with which to replace the lower spar cap, butterfly, lower splice plate, inboard web and spar web doublers. The butterfly and lower splice plate used are the “big butterfly.”
3. You may purchase a set of new current production wings. Our current wings feature upper and lower 4340 Chrome-Molly steel spar caps, and a 114 gallon fuel tank in each wing (228 gallons total). They have a safe life limit of 29,000 hours on the lower spar caps. The wing purchase
   includes all necessary parts, including: ribs, skins and spars, and all parts are brand new.

It should be noted that Thrush Aircraft, Inc. does not approve of altering any structural wing part in order to facilitate installation of a larger lower spar cap.  Our early experience attempting this fix clearly demonstrated that if the installation is not done very carefully and thoroughly, the modified wings could exhibit dangerous handling qualities – potentially leading to an accident.  Thrush does not make parts that will fit other lower spar cap installations and the alteration of existing parts without Thrush Aircraft, Inc. authorization abrogates any Thrush Aircraft responsibility for those wings.

If you have questions in regards to this AD, or to discuss the solutions available, please contact our Vice President Product Support & Development, Jody Bays, at (229) 789-0439, or This e-mail address is being protected from spambots. You need JavaScript enabled to view it. .

To purchase the spares, CK-AG-41 kit, or new wings please contact our Spares Manager, Ray Carter, at (229) 789-0453, or This e-mail address is being protected from spambots. You need JavaScript enabled to view it. .