Sec. 29.1011 - Engines: general.
(a) Each engine must have an independent oil system that can supply it
with an appropriate quantity of oil at a temperature not above that safe
for continuous operation.
(b) The usable oil capacity of each system may not be less than the
product of the endurance of the rotorcraft under critical operating
conditions and the maximum allowable oil consumption of the engine under
the same conditions, plus a suitable margin to ensure adequate circulation
and cooling. Instead of a rational analysis of endurance and consumption,
a usable oil capacity of one gallon for each 40 gallons of usable fuel may
be used for reciprocating engine installations.
(c) Oil-fuel ratios lower than those prescribed in paragraph (c) of
this section may be used if they are substantiated by data on the oil
consumption of the engine.
(d) The ability of the engine and oil cooling provisions to maintain
the oil temperature at or below the maximum established value must be
shown under the applicable requirements of §§29.1041 through 29.1049.
[Doc. No. 5084, 29 FR 16150, Dec. 3, 1964, as amended by Amdt.
29-26, 53 FR 34218, Sept. 2, 1988]