Joe Hull
Cozy Mk-IV N31CZ (65 hrs - Rotary 13B NA)
Redmond (Seattle),
Washington
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]
On Behalf Of Al Gietzen
Sent: Saturday, August 05, 2006
7:45 AM
To: Rotary
motors in aircraft
Subject: ***SPAM*** [FlyRotary]
It's officially an airplane
A high speed nose lift; a high speed crow hop; and finally
off and away around the pattern; the 20B powered Velocity, N755V maid its
maiden flight yesterday, 8/04/06. What an exciting milestone – even
though in this case I was watching from the ground as the test pilot did his
thing.
The engine performed well, and the pilot reported that all
handling characteristics were good. The flight was short, however;
because the oil temp was 10-15F higher than the limit I had set, and the pilot did
the right thing in abbreviating the flight so that can be evaluated and changes
made as necessary. All in all, with that as the only issue of note at
this point; it was a good day.
It’s such a common thing, isn’t it –
these cooling issues. The oil temp (downstream from the cooler) peaked at
230F, somewhat after the end of the climb (OAT about 80F); I guess it takes a
little while for the hot oil to get to the bottom of the 8 qt sump and back
through the cooler. The main concern was that the temp didn’t drop
more that 3-4 degrees as he went around the pattern, and after landing and
rolling out it was still 225F. Coolant temps peaked about 190F.
I had a video camera mounted reading the engine monitor
display which is great for review later. Unfortunately, even though I
have all sorts of instrumentation for doing diagnostics, in his focusing on
flight characteristics, and the concern about the high oil temp the pilot
forgot to push the ‘page up’ button; so the only data I have is
page 1. Regardless of further data, it seems clear that there is
insufficient air flow through the wing root oil cooler – a condition that
was not entirely unexpected.
Another major step in an on-going process.
Al