|
|
Steve, I can tell you that if you get the old spark plug "SAG", it will
happen at the moment mostly likely to require a new seat cushion. It
generally happens to me during full power (or nearly so) engine conditions.
Rpm will drop 200-300 rpm (depending if SAG on both or one rotor). Don't
know if you situation was due to SAG, but a new set of plugs clears it up
immediately. Sometimes, change the mixture control seems to help -
sometimes not. Most of the time it clears up after getting your heat
beating a bit faster.
Ed Anderson
----- Original Message -----
From: "Steve Brooks" <prvt_pilot@yahoo.com>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Saturday, December 04, 2004 9:23 AM
Subject: [FlyRotary] power sag
I went to South Carolina Thursday to replace the fuel regulator, and do
some
flying. I replaced the regulator, and ran the engine some on Thursday,
but
no flying because it was getting dark.
On Saturday, I went to fly, and had some trouble getting it to stay
running
due to the cold temperatures. I probably didn't keep it rich enough, long
enough. I taxied out to the far end of the runway (5000'), and took the
runway for take off.
As I accelerated to about 90 kts, I was just rotating when to power
dropped
substantially. I cut the throttle, and aborted the takeoff.
I don't know exactly what caused the sag. I pulled the throttle all the
way
back during the aborted takeoff, and the engine died. I have my idle stop
set a little low (400 RPM's), and usually don't pull it all the way off,
but
even when I do, it has never died.
I restarted it, and ran the power up to about 4000, and it seemed OK.
Another issue with my right main wheel bearing prevented me from making
any
more high speed runs. The right wheel has been making noise, and I was
trying to resolve it with the mfg, but during the aborted take off, it
really made allot of noise, and also vibrated pretty good at one speed, so
I
decided that I better get that fixed before doing any more flying.
I changed the fuel regulator, so I guess that it could have been some air
still in the fuel line, but the engine had probably run for at least 10
minutes prior to the take off roll. It also could have been some water,
though I've never found any to date during preflight. The engine was
running at 5 lbs of boost and about 5000 RPM's. It was about 45 degrees,
and the plane was accelerating very strong prior to the power loss. I
don't
know if it would have picked back up, but I was glad that it didn't happen
5
seconds later.
Steve Brooks
>> Homepage: http://www.flyrotary.com/
>> Archive: http://lancaironline.net/lists/flyrotary/List.html
|
|