Piston Idle Speed

[torquey401]

For the 172M, then the idle should be around 600RPM, the same as many other aircraft. If the idle is not right and it just came out of maintenance, snag it and take it back to the AMO. If they value your business it should be fixed ASAP. If it has cropped up over the inspection cycle, snag it and get it fixed and eat the 1 hour of shop rate if that is all it is. There may be other problems and if it continues to occur on its own, things will have to be looked at in depth. Or teach the student what a defect is and how to write one up.

Or teach the student the status quo that is prevalent in this industry.

Snag it and get it fixed. Not very difficult.

[Big Pistons Forever]

Part of the problem is pilots who don't know better. Sadly many instructors are not taught what is "right" for their airplane when they do their CPL course or even more unforgivably when they do their FI course . I did an FI rating for an FTU a few years ago. I was shocked to find that both C 150's flew sideways when you let go of the wheel. I talked to the AME and was told that nobody had complained in the 2 years they had been looking after the airplanes . So I explained what the problem was and two tweeks of the aileron rod ends later and then taking out almost all of the bend in the fixed rudder tab and the airplanes flew perfectly straight when you let go of the wheel. It sure is a lot easier to teach the fundamentals of flying when the airplane flies straight.........

If the idle on any airplane I fly is set at 1000 RPM my "flight" won't make it off the ramp. The airplane will just get taxied from the parking spot to the maintenance hanger, and the "defect" will get put in the JL.

[ruddersup?]

I like the slowest idle speed the engine can handle that won't stall out when back tracking on the runway in a strong wind. Anyone with me?

[cgzro]

As long as it wont stop in a spin
Gets your attention rather quickly!

[pistonpounder]

Idle speed should have been checked on run-up before take off, if this had been carried out student pilots would have had no trouble at all.

[tyndall]

Idle speed should have been checked on run-up before take off, if this had been carried out student pilots would have had no trouble at all.

Show me a checklist from a school that says what the idle speed is supposed to be and the tolerance allowed.

[pistonpounder]

well if you don't know what its supposed to be how do you know it to high.

[Colonel Sanders]

how do you know it (sic) to (sic) high

Easy. In a light trainer, when you approach at the recommended
speed and pull the throttle back to idle as you cross the runway
threshold, if the aircraft floats and floats and floats down the
runway in ground effect, you know the idle is set too high.

This makes the airplane really hard for the low-timers to land.

You really don't want to know how I set the idle. Considerable
harrumphing and letters to TC Enforcement are sure to follow.