Stache said:
I have to assume most of you are pilots. “There is nothing anywhere stating that engines must be run with the oil at full capacity.” Well I believe the POH/AMF has a pre-flight checklist and on the oil filler is a placard that states the amount of oil (8 quarts) as an example. Placards are covered in part 91 and following the pre-flight checklist is also a part 91 rule.
snip
Stache
From the Cessna 172SP POH preflight checklist in Section 4 Normal Operations:
"Engine Oil Dipstick/Filler Cap -- CHECK oil level, then check dipstick/filler cap SECURE.
Do not operate with less than five quarts. Fill to eight quarts for extended flight."
From Section 8 Handling, Service, & Maintenance
The engine lubrication system has a total capacity of 9 quarts of oil, with the oil filter accounting for 1 quart of that total. The engine oil sump (crankcase) has a capacity of 8 quarts. The engine must not be operated with less than 5 quarts in the sump. For extended flights, the engine oil should be at 8 quarts.
The oil filler cap is marked "OIL 8 QTS." There is absolutely NOT a placard that
requires 8 quarts on board, or that
prohibits operation with less than 8 quarts on board any more than the placards by each fuel filler that state "FUEL 100LL/100 MIN. GRADE AVIATION GASOLINE CAP. 26.5 U.S. GAL. USABLE CAP 17.5 U.S. GAL USABLE TO BOTTOM OF FILLER INDICATOR TAB" require me to depart with ONLY 26.5 or 17.5 U.S. gallons of fuel on board.
Looking at the information manual for a 1984 Cessna 172P, I find the same information regarding oil, with the exception of the fact that the sump capacity is 7 quarts instead of 8.
The preflight checklist of a 1975 Cessna 172M states "Do not operate with less than six quarts. Fill to eight quarts for extended flights." The Service Requirements section states "Capacity of Engine Sump -- 8 Quarts. Do not operate on less than 6 quarts. To minimize loss of oil through breather, fill to 7 quart level for normal flights of less than 3 hours. For extended flight, fill to 8 quarts."
The 1979 Cessna 152 has a maximum capacity of 6 quarts, and the preflight checklist says "do not operate with less than 4 quarts. Fill to six quarts for extended flight." Section 8 Handling, Service & Maintenance says "Do not operate on less than 4 quarts. To minimize loss of oil through the breather fill to normal flights of less than 3 hours. For extended flight, fill to 6 quarts."
Those last two give some indication of what Cessna considers "normal flight," in both cases calling it less than 3 hours.
In the 1973 Piper Cherokee Challenger Owner's Handbook, Section VI, Fuel And Oil Requirements, it states: "The oil capacity of the Lycoming O-360-A4A is 8 quarts, and the minimum safe quantity is 2 quarts."
Out of 5 aircraft, I found none that
require departure with full oil, and none that
prohibit departure with less than full oil. Quite the contrary, in fact, Cessna goes so far as to recommend it for at least two of these aircraft.
(he runs one of the better O/H shops in the country).
