TAS True Air Speeds in MPH miles per hour.
MXT7-180A 135mph tas
MX7-180A 140mph tas
MXT7-180 140mph tas
MX7-180 145mph tas
M7-235 O540 158mph tas
M7-235 IO540 160mph tas
M7-260 IO540 168mph tas
M7-420 195mph tas
M7-420 amphib 175mph tas

For my M5-235 with 8.50 tires it almost always comes out to:


knots true airspeed (KTAS)

75% 138 KTAS
65% 126 KTAS
55% 120 KTAS

Some variation with load, temp altitude etc but not more than 5 knots.

Never really seen less than 117 KTAS at 55%

Kirk

Jeremy, those are max level flight speeds, aren't they?

Max level flight at optimum altitude to achieve 75% power, standard temp and 7.00 x 6 tyres.
Some airplanes will exceed the figure by 2 or 3 mph.
The M6 will get the same speeds and the M5 slightly faster.
The oddball is M5-210TC, a factory type certified model with Lyc TO360, ten built around 1979/80, which can fly high and maintain manifold pressure, thus fly faster. In it's day TAS was 175mph.

Fuel burn in all these engines is between .45 and .48 lbs/hp/hour I think.
Prop efficiency can make a difference.

Based on the numbers Jeremy provide there appears to be a 13 to 25 mph TAS difference between a 180 and a 235.

Based on the average of the numbers others provided that difference is 13 to 35 mph indicated.

Actually, because of all the variables (tire size, props, temps, etc) involved it looks like the TAS and indicated are pretty close to being the same differences.

Wayne, when the weather gets a little better I would like to take you up on that offer. Thanks!

In a perfect world, the rpm, mp, and airspeed indicaters would be accurate however in reality we often have large descrepancies otherwise indicated airspeeds would correlate with TAS but not in linear fashion as TAS is a % of IAS which should be corrected to CAS but how many know their IAS/CAS exactly.

For 210TC.

Just to let you know, I am a fan. Vrrroooommm. Vrrroooommm.

Scott

taildragger wrote:
For 210TC.

Just to let you know, I am a fan. Vrrroooommm. Vrrroooommm.

Scott

That is an unusual looking Maule!

I use 105 KTAS or 120 mph for my 1986 MX-7-180 @ 10 gph with 8.00-6 tires and stock Hartzell 76" CS prop. Looking at the 0-360A/C series performance chart shows that to be around 68% power at 3000' with 21.5 MP and 2330 RPM.

Andy

Out of curiosity have any of you with fuel flow meters figured out MPG? I ask because I have and to my surprise the C-210 and my M-6/235 get almost identical mileage.
The myth for Maules of course is that if the 235 is flown at the same speed as the 180, then the fuel burn is almost identical.

120 MPH, 8 gph when LOP = 15 MPG

I get the same thing as Maule 9V.

I'm getting 100kts (115mph) for 30-35L/hour (or a 8 gals). That's pretty slow, but keeps me in the air for 9 hours (longest single flight so far 7.1!).

I was hoping to see that I could improve my figures, but it looks as if I'm doing okay!

So, if I can fly to empty in 9 hours, that gives me a range of 900nm - I believe no other Maule type can make that range (but they'll make not too much shorter distance in a much faster time)?

Safe flights all, Sam.

My M5 180 does 112 knots at 24 squared 5,000 ft. The M5 wing is a little shorter than the others and so gives a better airspeed. The indicated is 128 mph

I don't often fly high but recently I cruised at 9,500', 12 degrees C OAT, wide open throttle (WOT), 2500 rpm, 9.0 gph leaned to peak EGT due to the low MP. CHTs were all about 360 F. The aircraft was about 2300 lbs. I was suprised to see a TAS of 144 mph, (122 IAS). This is an M5-210C.