From;
https://www.sensenich.com/company/: Sensenich Propeller was established in 1932 to manufacture fixed pitch wood aircraft propellers for the growing aviation market. In 1949 we began to manufacture wood propellers for the burgeoning airboat market. Aluminum propellers for aircraft was added to our product line in the 1950’s. During the 1960’s the use of UAV’s became prevalent and Sensenich was right there with propellers for the new industry. In 1999 We began our highly successful line of ground adjustable composite propellers for Airboat, Aircraft and UAV’s.
This fits my view of events: The Army -1 lists a "Sensenich 72x44 propeller," the company produced "MANUAL OF MAINTENANCE" says that the aircraft has a "Sensenich 72x44 wooden propeller" as listed in the performance charts. The Original CAA T.C. (NOT TCDS!!) lists a "Sensenich 72C44 propeller." I submit that the three are the same.
The aircraft was built as an observer for the Army. It never had an engine driven electrical system. It did have a strut mounted wind driven generator, radios, antennas, and batteries that weighed 40 or so pounds. When surplussed, the Army removed the radios. The rest came out when it was civilianized.
(Note: The main wheels are 3” aft of datum, the leading edge of wing, and at flying attitude, the tail wheel is 186” aft of the main wheels or 189" aft of datum-- facts not considered.)
From 1947 Reweigh: CAA form 309:
SECTION I - WEIGHT
A. EMPTY WEIGHT AS WEIGHED IN LEVEL FLYING POSITION
SCALE TARE NET
RIGHT WHEEL 331 0 331 C. G. AFT C.L. AXLE 717.5 / 186 (53.5) = 13.87
LEFT WHEEL 333 0 333 C. G. AXLE AFT L.E. WING = 3
TAIL 58.5 5 53.5 C. G. AS WEIGHED IS AFT L. E. WING = 13.87
TOTAL 723.5 5 717.5
B. EMPTY WEIGHT AS WEIGHED INCLUDES THE FOLLOWING
1. Standard Equipment:
ITEM
PROPELLER AND HUB SENSENICH 72C TC 170 SER 11996
FIRE EXTINGUISHER
AIR SPEED
ALTIMETER
OIL PRESSURE AND TEMPERATURE GAUGE
TACHOMETER
IGNITION SWITCH
WHEELS AND TIRES (Shinn 6C2HB TC63 Firestone 6.00-6 PLY:2)
TAIL SKID AND SPRING
SAFETY BELTS (2)
SEAT BOTTOM CUSHIONS (2 LEATERETTE)
FIRST AID KIT
AIRCRAFT AND EIGlNE LOG BOOKS
2. Items for which approval as optional equipment is desired:
ITEM WEIGHT ARM
Steerable Tail Wheel 5 195
Brakes 6.8 3
Compass 1 --4
Cabin Heater 1 --28
Engine Primer 1 --11
Carpet 2 9
(The above propeller was not mounted nor included in the sale. And there is another Error, obviously the aircraft doesn't have a tail skid and a tail wheel.)
SECTION II - BALANCE
MOST FORWARD C. G. LOADING CONDITION
ITEM WEIGHT ARM MOMENT
WEIGHT EMPTY 756.8 13.87 10497
OIL ( 1 GAL.) 7.5 --37 --227
FUEL ( 13.5 GAL.) 81 --16 --1296
PILOT 170 35.8 6086
TOTAL 996 15.12 15060
C. G. AFT L. E. M.A.C. 15.12 - .24 = 14.88”
C. G. PERCENT M.A.C. 14.88 x 100 / 59 = 25.22 %
(Hmmm? They weighed the airplane and recorded the empty weight as 717.5 pounds. "B." says, "EMPTY WEIGHT AS WEIGHED INCLUDES THE FOLLOWING," which I believe. Because it's quite close to what it weighs today when changed items are backed out. But then the Balance part lists the empty weight as 756.8, the pre-re-weight empty weight. )
"My" 1942 Taylorcraft (a TG-6 converted to a DCO-65 in 1947) has an ancient 72C44 on it. In spite of what I am told Sensenich didn't prefix wood propellers "W" in 1947. Why would they? They didn't make metal props until the 50's. Those I seek answers from don't know this. And nobody ever taught them to think, just to parrot. They say "we have always..."
No, you haven't, maybe you have since 1958... The FAA is worse, they took the original T.C.s and altered them-- adding material errors. It's a good thing people don't actually follows the rules. That would be unsafe. The "notes" on the paper copies of the Propeller T.C. (thanks Aaron) have been omitted from the electronic version.
On the paper copy the 72C prop is on the airframe approval and the airframe on the prop approval. On a subsequent paper version the nomenclature change is explained. But it is nowhere to be found on the "new official copy."
