89-08-08 BOEING: Amendment 39-6191. \n\n\tApplicability: Model 737-100 and 737-200 series airplanes, certificated in any category, which presently do not use nose gear compression logic to enable thrust reversers. \n\n\tCompliance: Required as indicated, unless previously accomplished. \n\n\tTo ensure timely deployment of reverse thrust when landing under adverse weather and runway conditions, accomplish the following: \n\n\tA.\tWithin 18 months from the effective date of this AD, install an FAA-approved modification to the Air/Ground Sensing System which causes the thrust reverser logic to be enabled by nose gear strut compression in addition to the present logic of the right main gear oleo compression. \n\n\tB.\tAn alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. \n\n\tNOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who may add any comments and then send it to the Manager, Seattle Aircraft Certification Office. \n\n\tC.\tSpecial flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of the modification required by this AD. \n\n\tThis amendment (39-6191, AD 89-08-08) becomes effective on May 10, 1989.