R 44/ R 22 MAP calculations

[Steve-O]

I've heard several different takes on this subject, and I'm not sure what to make of it. I've had some instructors tell me that you have to re-calculate your MAP limit once you are at your cruising altitude, while others are satisfied that calculating it once before takeoff is sufficient. I would appreciate any opinions on this topic. Thanks.

[Helipilot PTK]

My flight instructors had me calculate it before takeoff, I have never recalculated it while in cruise flight, they have asked me what is was while inflight but I never had to recalculate it. I am in no way all-knowing on this subject and there are many more qualified individuals that can explain this to you on here, that is just my personal experience.

[RagMan]

Should be recalculated for whatever conditions you are operating in/at. That's alright if you calculate it before takeoff and stay around the airport where the conditions are present, but if you stray out and do some off airport landings where they may be a change in temperature or pressure altitude, you're going to want to recalculate your performance numbers, because especially in the real world, those numbers will change.

[ADRidge]

Should be recalculated for whatever conditions you are operating in/at. That's alright if you calculate it before takeoff and stay around the airport where the conditions are present, but if you stray out and do some off airport landings where they may be a change in temperature or pressure altitude, you're going to want to recalculate your performance numbers, because especially in the real world, those numbers will change.

 

Which is why my scan includes the OAT readout. I picked that one up in Mike's C&E seminar, and it certainly makes sense. Granted, any temp/altitude changes that will be made in south Texas probably won't have TOO much bearing on MAP changes, but when you start getting into mountainous terrain, I definitely understand why a person might want to reconsider those calculations every so often.