Real world performance?

[Jesse]

I will be flying an RV-6A from TX to SC on Thursday. It is 180HP with a Hartzell blended airfoil prop. I know there are variables, but for those who are flying with this specific configuration, what cruise TAS and fuel burns are you seeing at, say, 11,000'?

Thanks in advance.

[Jesse]

I forgot to mention, it's carbureted.

[MikeyDale]

Mines a taildragger IO360. I burn about 8.3 gph cruising 157 kts TAS running 50 deg LOP @ 8k. Not sure if its typical for a RV7 or my inexperience at LOP but I get better speed on less fuel burn at lower altitudes.

[n468ac]

Originally Posted by Jesse

I will be flying an RV-6A from TX to SC on Thursday. It is 180HP with a Hartzell blended airfoil prop. I know there are variables, but for those who are flying with this specific configuration, what cruise TAS and fuel burns are you seeing at, say, 11,000'?

Thanks in advance.

O-360 fixed pitched prop. 165kts true at 9.1 gph 10,500 to 12,500.

[Ken Harrill]

My RV6 with O-360, CS prop will cruise at 155-160 kts @ 10,000 ft burning 8 gph lean of peak. Sometimes more, sometimes less depending on load. This is at about 65% power.

[ChiefPilot]

Wow - the variability here is pretty interesting. I'm wondering what some of the variables might be.

• Is electronic ignition, which may reduce fuel flows by 1-1.5GPH or possibly more present?
• Are fuel flows being measured instantaneously (i.e. fuel flow meter) or via block (fuel burned for the flight divided by flight time)?
• Has the airspeed indicated been calibrated, and if so what is the margin of error?

In my case, RV-6A w/IO-360-B1B, dual P-Mags, Hartzell 74" BA prop, I see 6.2GPH at 155KTAS at 11k density altitude. Pushing it up to 165KTAS will cost me 7.9GPH. 175KTAS will cost me 8.9GPH. Vmax at 11k DA was 179KTAS, which cost 9.6GPH. Fuel flows are measured via a Dynon EMS using the "Red Cube" located between the throttle body and fuel divider and are LOP except for Vmax, which was leaned for best power. True airspeed values are taking the 2.8% error at these altitudes shown by the airspeed indicators into account as well.

[Jesse]

Well, it turns out I got about 155ktas on about 7.5-8gph at 11k and about 165ktas on ??? At 9k. No fuel flow and only a single EGT needle, so not very easy to dial in. The ??? Is because I didn't fill up after landing, so I don't know what it burned. Thanks, all, for the help. I was hoping to make it nonstop, and maybe could have by pulling back a little, but with a faulty left tank gauge and no flow meter, I wasn't going to push it.

[N941WR]

When I was commuting between Houston, TX and Greenville, SC with my -9 I would stop half way and top off. Except that one time when I was up at 15.5 being pushed by a 50+ knot tailwind and made it nonstop and only burned 24 gallons.

You did good.

Where in SC did you drop it off?

[plehrke]

Just seeing this thread so already OBE but still thought I would throw my numbers out.
RV-6A/IO-360-B2B/FP 85" pitch
@ 11Kft
75% power I see 175 KTAS burning 9.8 leaning to peak EGT
65% power I see 164 KTAS burning 8.9 leaning to peak EGT

[Jesse]

Originally Posted by N941WR

You did good.

Where in SC did you drop it off?

S17 near Augusta.