§29.1041 General

(a) The powerplant an d au xiliary p ower u nit cooling provi sions m ust be abl e t o maintain the temperatures of powerpl ant com ponents, engi ne fluids, and auxiliary pow er unit com ponents and fluids within the temperature limits established for these components and fluids, under ground, water, and fl ight operat ing condi tions for which certification i s request ed, and aft er normal engine or auxiliary power shut-down, or both. (b) There m ust be cool ing provi sions to maintain th e flu id tem peratures in any power transmission within safe values under any critical surface (ground or water) and flight operating conditions. (c) Except for ground-use-only auxiliary power uni ts, com pliance wi th sub-paragraphs (a) and (b) must be shown by flight tests in which the temperatures of sel ected powerpl ant com ponent and auxiliary power unit component, engine, and transmission fl uids are obt ained under the conditions prescribed in those paragraphs.