78-08-01 HAWKER SIDDELEY AVIATION LIMITED: Amendment 39-3180. Applies to BH/HS 125-600A airplanes, certificated in all categories.
Compliance required within one month after the effective date of this AD, unless already accomplished.
To prevent possible inability to activate the engine blow-off valve switches in the event that birds are ingested into the engines on take-off, accomplish the following:
Remove the existing switch guards for the engine blow-off valve switches and replace with the new design guard, P/N 25-6 NF 2629, in accordance with the section entitled "Accomplishment Instructions" and the associated drawing, contained in Hawker Siddeley Aviation, Ltd. Service Bulletin 75-3(2580), dated June 21, 1977, or an FAA-approved equivalent.
This amendment becomes effective May 10, 1978.