I hope everyone had a good Christmas.
My query relates to an issue which caused my blood pressure to increase on 2 out the last 3 flights, as follows:
A sudden 150-200 rpm drop in engine RPM at cruise power, which quickly recovered and only happened once on each flight.
Engine: Rotax 912 ULS 780hrs total
Prop: 3 bladed VP with 'auto' and 'manual' modes
Fuel: Ultimate unleaded
Service history: in date and iaw MOGAS requirements
Conditions:
Cruise 3000'
Cruise power, so approx 23" and 5000 rpm
Carb heat had been regularly applied
OAT quite cold prob around -5 deg C
Prop set in auto mode 'hysteris' 75rpm
Calm air
All other engine indications normal
On both occasions this happened after approx 30 mins of flight
Has anyone experienced similar or has any ideas as to what the cause might be?
The engine has been running fine up until the last 2 out of 3 flights.
Thank you.
Simon
Edinburgh
My query relates to an issue which caused my blood pressure to increase on 2 out the last 3 flights, as follows:
A sudden 150-200 rpm drop in engine RPM at cruise power, which quickly recovered and only happened once on each flight.
Engine: Rotax 912 ULS 780hrs total
Prop: 3 bladed VP with 'auto' and 'manual' modes
Fuel: Ultimate unleaded
Service history: in date and iaw MOGAS requirements
Conditions:
Cruise 3000'
Cruise power, so approx 23" and 5000 rpm
Carb heat had been regularly applied
OAT quite cold prob around -5 deg C
Prop set in auto mode 'hysteris' 75rpm
Calm air
All other engine indications normal
On both occasions this happened after approx 30 mins of flight
Has anyone experienced similar or has any ideas as to what the cause might be?
The engine has been running fine up until the last 2 out of 3 flights.
Thank you.
Simon
Edinburgh
