Bayou Bert
Well Known Member
My RV9A "Pearl" now has 13.9 flight hours in Phase I.
From the very first lift off, the prop has surged and was still
doing it yesterday when we flew.
Info on plane
Engine: O-320-D2G with FI
Starting Governor: MT P-860-4 and was not one in the batch with problems.
Prop: Hartzell C2YL-1BF/F7663-4
What has been done so far:
Governor
The governor was a new MT put on the engine when it was build.
When the problem started (first flight) I removed governor and sent to
MT in DeLand, FL. The replaced a spring and polished a shaft and said
the governor met MT requirements.
Re-installed and found no difference.
Then friend had a rebuilt Woodward which was installed.
No change on the RPMs surging.
Prop
Prop was purchased (rebuilt) for a Northwest coast prop shop in 2014.
When problems started, prop was removed and taken to a reputable prop
shop in the Houston area for a quick check. Static balance was off slightly
and corrected then on the bench, air applied and all angles etc checked.
When I left, prop met Hartzells specs.
Since then prop was dynamic balanced with final reading of .05.
The static stops on the prop are set so that at full power on the ground
RPMs show 2650/60. Two tacks, checked to be correct during prop
balance and found accurate.
First chart is the first 50 seconds of takeoff showing MAP in orange and
RPMS in Blue.
Software takes a shot of data twice each second so distance from dot
to dot is one half a second.
Notice the big sag, sure gets your attention on take off.
On All charts, RPM scale on left, MAP scale on right.
Second chart is at 3500' then setting up 25/25, then moving the throttle
around to see RPM response. Notice RPM does not go back to exactly 2500
between moves
Third chart shows later in flight at 2400 RPM and me reducing the throttle and the RPMs going up!
I am now to the point I don't know what to do next. This is taking a bunch
of the fun out of Phase I having to worry about the engine/prop all the
time. This is the first CS prop I have flown behind. The person who has
flown several flight for me is a 30+yr A/P, IA and has thousands of hours
in everything from Cubs to Gulfstreams and he says he never seen one
behave like this one.
Sooooo.....that's the story to this point.
ALL...comments, questions, suggestions more than welcome.
From the very first lift off, the prop has surged and was still
doing it yesterday when we flew.
Info on plane
Engine: O-320-D2G with FI
Starting Governor: MT P-860-4 and was not one in the batch with problems.
Prop: Hartzell C2YL-1BF/F7663-4
What has been done so far:
Governor
The governor was a new MT put on the engine when it was build.
When the problem started (first flight) I removed governor and sent to
MT in DeLand, FL. The replaced a spring and polished a shaft and said
the governor met MT requirements.
Re-installed and found no difference.
Then friend had a rebuilt Woodward which was installed.
No change on the RPMs surging.
Prop
Prop was purchased (rebuilt) for a Northwest coast prop shop in 2014.
When problems started, prop was removed and taken to a reputable prop
shop in the Houston area for a quick check. Static balance was off slightly
and corrected then on the bench, air applied and all angles etc checked.
When I left, prop met Hartzells specs.
Since then prop was dynamic balanced with final reading of .05.
The static stops on the prop are set so that at full power on the ground
RPMs show 2650/60. Two tacks, checked to be correct during prop
balance and found accurate.
First chart is the first 50 seconds of takeoff showing MAP in orange and
RPMS in Blue.
Software takes a shot of data twice each second so distance from dot
to dot is one half a second.
Notice the big sag, sure gets your attention on take off.
On All charts, RPM scale on left, MAP scale on right.
Second chart is at 3500' then setting up 25/25, then moving the throttle
around to see RPM response. Notice RPM does not go back to exactly 2500
between moves
Third chart shows later in flight at 2400 RPM and me reducing the throttle and the RPMs going up!
I am now to the point I don't know what to do next. This is taking a bunch
of the fun out of Phase I having to worry about the engine/prop all the
time. This is the first CS prop I have flown behind. The person who has
flown several flight for me is a 30+yr A/P, IA and has thousands of hours
in everything from Cubs to Gulfstreams and he says he never seen one
behave like this one.
Sooooo.....that's the story to this point.
ALL...comments, questions, suggestions more than welcome.