Pearl Harbor Defense

Chris Mark wrote:

From: Guy Alcala

in 1941,
they started to see just how much they could safely stretch the fuel economy
of the Zero, individually and then in larger groups. Ten hour missions
became routine, then 11 and eventually they were able to stay in the air for
12. Okumiya describes this in "Zero!", with average fuel consumption
dropping to 21 gal./hr. and Saburo Sakai holding the record at only 18
gal./hr.

Interesting. The Wright R-2600 engine burned about 75gph at 60 percent power.
Any details on how the Japanese achieved such frugal fuel consumption figures?
What was "normal" fuel consumption for the Zero?

I have a vague memory of reading 30-35gal./hr. somewhere, but don't hold me to
it. The A6M2 had the Sakae 12 engine, which was only rated at 950 hp or so. When
they got the A6M3 Model 32 in the Solomons, which had the more powerful Sakae 21
engine of 1,130 hp (and slightly less fuel) plus clipped tips, they found that its
range was inadequate to make it from Rabaul to Guadalcanal and back (it was
pushing it for the A6M2), which IIRR was something like 550 sm one way. They
built intermediate strips down the Solomons (Buin, etc) so that it could get there
and back, and put the A6M3 Model 22 with increased internal fuel and the full
wingspan (non-folding, like the first production model, the A6M2 Model 11) into
production for land use.

The USN found that for carrier operations, overall they could plan on R-2600s
burning 45-50 gal./hr average per sortie (which includes lots of low speed loiter
for landing and ASW patrol) depending on whether it was in an Avenger or a
Helldiver, while the R-2800 in the Hellcat burned about 75 or so (same landing
loiter, CAP loiter). The exact mix of sortie types flown would affect the
average, but as far as planning for carrier AVGAS replenishment needs, that gave
them good numbers.

Guy