Hi All, have an RV7 with IO-375/Vetterman 4-2 crossover and Hartzell BA 72" CS in phase 1 and think to limit the forward travel of the blue knob to reduce the max RPM to let's say 2400. maybe sounds idiotic but let me explain...
we have some strict noise regulations in germany (people seem to be more noise sensitive than in north america). as i understand there are three noise categories when it comes to registration of GA aircraft... bad, medium and ok. i'm probably in the catastrophic category. i love my setup but she's loud. something will happen on the exhaust with mufflers but that will likely not be enough.
lately i made a takeoff with 2400 RPM, noticeable difference but still runs and climbs like crazy. with 2400 she's still overpowered and i'm ok with running a bit oversquare as lycoming doesn't state MAP limitations at specific RPM for the -M1S (which is an M1B with cold air sump) and the guys with fixed pitch setup for cruise seem to be happy.
some limit the max RPM directly at the governor... i will not do that. in the air force i was a technician for the tornado. i remember the pilot was able to move the thrust levers freely to "max reheat", but there was an further stage (combat) with even more afterburner. that combat mode had to be avoided as it was very bad for the engines/taxpayer, not so important if the MiG is chasing you.
there was some kind of a seal at the thrust levers that the pilot could push over to reach combat and i am thinking to do something similar at the blue knob. a latch or something that is semi permanent and one could apply max RPM quickly if it's really needed. I have the standard Vans blue vernier cable between MAP and mixture.
any ideas how to do that?
Best Regards
Kay
we have some strict noise regulations in germany (people seem to be more noise sensitive than in north america). as i understand there are three noise categories when it comes to registration of GA aircraft... bad, medium and ok. i'm probably in the catastrophic category. i love my setup but she's loud. something will happen on the exhaust with mufflers but that will likely not be enough.
lately i made a takeoff with 2400 RPM, noticeable difference but still runs and climbs like crazy. with 2400 she's still overpowered and i'm ok with running a bit oversquare as lycoming doesn't state MAP limitations at specific RPM for the -M1S (which is an M1B with cold air sump) and the guys with fixed pitch setup for cruise seem to be happy.
some limit the max RPM directly at the governor... i will not do that. in the air force i was a technician for the tornado. i remember the pilot was able to move the thrust levers freely to "max reheat", but there was an further stage (combat) with even more afterburner. that combat mode had to be avoided as it was very bad for the engines/taxpayer, not so important if the MiG is chasing you.
there was some kind of a seal at the thrust levers that the pilot could push over to reach combat and i am thinking to do something similar at the blue knob. a latch or something that is semi permanent and one could apply max RPM quickly if it's really needed. I have the standard Vans blue vernier cable between MAP and mixture.
any ideas how to do that?
Best Regards
Kay