Pretakeoff and Takeoff Ops With Respect to Oil Temperature..

[dannyb]

Hi,

Flocker and I have had some dialog about this, but I wanted to get a gauge on what other's input might be.

In regard to oil temperature and engine management warmup and pre-takeoff, my P2008 with a 912iS POH outlines:

> Limit engine RPM to 2,500 RPM max until oil temperature reaches 120 F.
> Okay to go to 4,000 RPM above 120 F.
> Wait until oil gets to 194 F to perform Lane Ignition and Fuel Pump checks.
> Subsequently, take off is performed after the checks with the oil temperature is above 194 F.

I checked the ROTAX 912iS Operation Manual. They outline limiting RPM to 2,500 until 120 F and then go into the Ignition and Fuel Pump checks with no mention of waiting until 194 F. "Normal" operating range is 194 F minimum... but does that preclude takeoff until 194 F?

The POHs for the 912iS powered Bristel and RV-12 describe what is in the ROTAX Operation Manual; limit RPM to 2,500 until 120 F, perform Ignition and Fuel Pump checks, no specific mention about take-off oil temperatures.

How do you handle this?
Danny

[bigmo]

I have to think that's a typo. Of all the hours on Vans & the Rotax forums, I've never seen mention on that high of a pre takeoff oil temp. 50C is the standard, which is 122F, not 120F...but I guess Rotax found 120F easier to memorize. In the winter, I rarely get above 194F even with 3/4 of my oil cooler covered.

From all the discussions on the Rotax forum, 120F oil assures all the metals in the motor are warm enough for the stresses of takeoff power.

Is there a perhaps a newer manual with a temp correction/revision?

[dannyb]

Good catch on the 50C really being 122F and not 120F...

From the ROTAX manual for the 912iS...





From the TECNAM Manual Pretakeoff Oil Temperature...




d.

Attachments:

[dannyb]

I had a nice conversation with a tech at a well-known and highly respected Rotax Service Center about oil temperatures at takeoff. I explained to him about the Tecnam POH procedures for run-up and takeoff temperatures. He said to follow the Rotax procedures... 120F, perform the Lane and Fuel Pump checks, go fly.

Danny B.