Thielert Engine Owners Group

Regarding Docket No. FAA-2009-0753; Directorate Identifier 2009-NE-31-AD, we sincerely request the AD to be modified to state under Actions and Compliance (e)(4) "If any evidence of a failed cooling nozzle is found, inspect and repair cooling nozzle before further flight." Diamond Aircraft Industries has performed tests on these engines with no cooling nozzles and found that after 100 hours of operations with no cooling nozzles the engines did not sustain any damage and could be returned to service by simply replacing the broken cooling nozzles. Engines that have been repaired and returned to service continue to operate with not further problems. Certified cooling nozzles are available from Diamond Aircraft Industries which allow for a certified repair of a broken cooling nozzle. Furthermore, the requirement to remove the engine from service places an undue burden on owners and which are not represented in the "Costs of Compliance" sections. Each engine removed from service would create an unnecessary cost of $45,000 in addition to the cost of the inspection. On behalf of the 167 owners represented by the Thielert Owners Group, which represent a total of 301 Thielert engines, we respectfully ask that this AD be modified to allow for the repair of any engine where evidence of a failed cooling nozzle is found. Thank You Vilis Ositis Thielert Engine Owners Group http://www.thenog.org VOsitis@LakeWW.com 925 989 8940