UH-1N Category II Climatic Laboratory Tests.

• Main Authors: Ford, James A., Nelsen, Gary L.
• Other Authors: AIR FORCE FLIGHT TEST CENTER EDWARDS AFB CA
• Format: Text
• Language: English
• Published: 1971
• Subjects: Helicopters; THERMAL STRESSES; ARCTIC REGIONS; DESERTS; AIRCRAFT ENGINE OILS; LEAKAGE(FLUID); HYDRAULIC EQUIPMENT; AIRCRAFT HEATERS; AIRCRAFT CABINS; SEALS(STOPPERS); ROTOR BLADES(ROTARY WINGS); GEARS; CATEGORY 2 TESTS; H-1 AIRCRAFT; M-94 GRENADE LAUNCHERS; UH-1N AIRCRAFT; XM-94 GRENADE LAUNCHERS; Arctic
• Online Access: http://www.dtic.mil/docs/citations/AD0891288; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0891288

The UH-1N was evaluated at extreme temperatures in the Eglin AFB Climatic Laboratory to identify problems likely to occur in arctic and desert regions of deployment. The UH-1N and its subsystems operated satisfactorily in the laboratory environment from 110 degrees F to -55 degrees F. Major problem areas consisted of severe engine oil leakage at -65 degrees F and 90-degree gearbox oil leakage at 125 degrees F. Except for these leaks and a leak in one stabilizer bar viscous damper, the materials used to seal lubricants and working fluids were adequate; particularly in the hydraulic system where no leakage occurred at any test temperatures. The capability for self-contained starts as stated in the UH-1N Detail Specification was considered marginal at or below 0 degrees F and did not exist at -25 degrees F. The bleed air heater did not maintain the 40 degree F mean temperature specified in the UH-1N Detail Specification; however, the cabin was comfortable at -55 degrees F outside temperature. In general, the XM-94 weapon system operation was satisfactory at all low temperatures tested, including -65 degrees F. (Author) Includes attached Addendum.