FES vs Gas Engine – Finding a Thermal?

my experience has been that the vibration (and possibly disturbed airflow) caused so much wild gyration in the vario readings that it seemed pointless to try to determine if I was flying into rising air, so I just climbed first, then shut down the engine and started a thermal search.

Hi Frank,
My ApisM is equipped with a pneumatic toggle switch that disables the rear-fin-mounted Total Energy probe. It is vital that you have this. It completely eliminates the wild vario readings so that you can detect thermals and circle in them with the engine on. This greatly boosts your climb rate and you get to shut off the engine much quicker. When the engine is retracted just flip the switch and you are back to TE mode.

On Thursday, August 24, 2017 at 4:29:01 PM UTC-4, V1 wrote:
While reading the FES article in June Soaring (yes, I’m behind in my reading), I noticed the author’s comment about searching for a thermal while FES was running, then shutting down FES as he started to climb. This is a topic I don’t recall seeing discussed in any FES vs gas comparisons.

In my Solo-powered Ventus 2cxT, my experience has been that the vibration (and possibly disturbed airflow) caused so much wild gyration in the vario readings that it seemed pointless to try to determine if I was flying into rising air, so I just climbed first, then shut down the engine and started a thermal search.

My question – do others have experience to share about their ability to find thermals while a sustainer or self-launcher (either gas or electric) was running? If electric has an advantage here, this could reduce the run-time needed and conserve “fuel�.

- Frank

On the PIK I have a standard TE probe going to
a gust filter and then the Winter vario.

This is good enougt with the engine running
to evaluate a thermal.

JMF