MaxFacts: “I feel the need for Speed”.TBM governor, Bad Juju!

TBM 930 – World’s Fastest Single Turboprop Aircraft!
Daher today unveiled this month the expanded range of its very fast turboprop aircraft family, which now consists of the TBM 900 and 930 version – each of which retain the performance and technical features that have made the TBM 900 a business aviation success. In 2014, the TBM 900 was introduced as an improved version of their TBM 850 with 26 modifications including winglets, a redesigned air intake and a 5-blade propeller, for better aerodynamics and performance. Maximum cruise speed was increased **330 kn at 64 US gallons per hour with a range of 1,730 nm (with 45-minute standard IFR reserves)

MaxSez: Seems the speed envelope for the IF TBM has a governor installed. 330kn/380mph/Mach.5 by the book at cruise but ours Overspeed’s above 265kn above and beyond 12kAGL even less than 265kn at 30kAGL Cruise (My 3 Overspeed Test Violations prove it)

Is a tweek to the IF TBM Speed parameter a good thing for our “World’s Fastest Single Turboprop Aircraft”. A vote is a yes!
Thanks for yr vote, No vote or question my logic, a pox on you; Max

Is Mach based on airspeed, true airspeed, or ground speed?

The numbers you are referring to are in GS it seems. In your screenshot you’re at M0.50 and 330knts GS.

The reason I ask, I’ve noticed some airliners, the governor continues to come down, even as ground speed decreases, this generally happens around 32,000 feet I think. I’ve wondered why? Does the tbm do this as well?

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@David_Driggers… IF calibrated, see the photo speed strip. Max

I’m asking as you increase altitude, maintaining the same KIAS speed, does the governed speed decrease?

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The Tetrasonic TBM! (I made up the word tetrasonic but it just came up like a random word)

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@Trio… Believe IF ground speed on the tape is MPH… Just give me all you got, I’m tired of being passed by SR-22’s LOL…
Warm Regards Spoil Sport… Max

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I’ll give ye a vote 👍

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I believe the current model accurately depicts how the IRL TBM operates. Ground speed isn’t mph.

via the TBM-930 Manual

@Trio, “Facts” we don’t need no stinking facts”!!! See the Quote.
Warmer Regards, Max

(I relish robust interaction and fishing on the Forum)

😂 fair enough, no one likes getting outrun by an SR22.

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@schyllberg. MaxAsks: Pls Close this Topic it served its useless function and was shot down in flames… Thanks, Max

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The reason is the 330kts cruise you read is in TAS. 330kts IAS would be wayyy over mach .5 (and faster than mwhat most airliners do). I don’t actually see a problem here.

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The overspeed limit is an envelop formed by a fixed IAS (usually 350) and mach limit. At higher altitudes, the IAS-TAS ratio decreases so the mach limit become lower than 350 IAS.
Usually it kicks in at around 26000ft. I think you are noticing it at over 30000ft cuz windaloft is down.