Barney,
We have changed the software so it would not count
the occasional spike caused by the tachgen as an event during the initial
testing development of the TSLM and with the over 40 planes
flying with the TSLM have not had any complaints.
We have downloads showing Lancairs with significant
over temps , N2 in excess of 2080 rpm by as much as 300 plus rpm and over torque
during test flights for a couple of seconds at a time and usually the over temp
, over speed and over torque happens simultaneously. According to our customers
these over temps are done by various pilots including Lancair test pilots.
Diemech Turbines has this data recorded on file, in most cases Diemech
Turbines found it necessary to open up engines to repair the
damage.
It is also important to note that with regards to
using the 84 inch prop especially over speeding the N2 on landing on a
short strip at high elevation with a Lancair IV T that you have Beta
Limiting activated in the configuration and wired up, as you can easily
exceed 1900 RPM ( Walter Manual ) in Beta / Reverse during
landing.
It has been demonstrated on a plane with a
99 inch prop as well.
Regards,
Maurits
----- Original Message -----
Sent: Wednesday, May 24, 2006 4:43
PM
Subject: [LML] Re: turbines over temps
& rpm
Bill
I have not heard of any test pilot over temping
or over revving Walters. I do know that the new TSLM that is installed
on most Walters now records engine parameters. The problem with these
records is that there seems to be spikes in the system that it also
records. These are split second spikes that are errors but it records
them anyways due to the accuracy of the system. I did notice that on my
turbine we had to put quite a few capacitors in the wiring to reduce these
spikes that were occurring. We noticed things like hydraulic pump
actuation causing ITT spikes and various other power draws doing the same
thing until we put these capacitor "filters" in the wiring to get rid of these
power spikes and false readings. I believe that this may have something
to do with these rumors as we were talking about these issues with the TSLM at
the Sebring annual recurrent training course. These power spikes
effected quite a few of my engine readings until they were rectified.
The Walter ITT readings are always bouncing around anyways and are never as
steady as what you would see from a Pratt.
Barney Britton
IVPT C-GPOA
----- Original Message -----
Sent: Wednesday, May 24, 2006 5:06
PM
Subject: [LML] turbines over temps
& rpm
Can anyone on the list enlighten
me to which test pilot is over temping and over revving the Walters on the
east coast –rumor . Also a test pilot gear up landing in Florida several
mounts back –would like details on these if known . This is something that
seems to be a rumor but would like a clarification Bill Maddox
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