Lycoming-powered Diamond DA42 Demo

Did he say 10.8 GPH per side?? He was talking about climb rates just before, was the 10.8 in a climb. I am assuming.

Wow, your O-360s only burned 5.5 gph each? Impressive considering my O-200 burns 4.5gph at cruise. Lycoming published specs say that best comsumption is .43 lb/Hp-hr which translates to approx 11.5 gph. I'm very sure they are talking about 10.8gph a side at a high power cruise.

oops, bad math, I figured it at Jet-A weight. Habbit. Its actually 12.85gph for avgas @ 6.02lbs.

The Twin Comanche has O-320's not 360's, which accounts for the lower fuel flow. My calculations were not by guage or fuel flow meter, which was not really reliable, but I calculated total time flown and total gals to fill up. That gave me an overall fule burn rate. One more thing: we used imperial gallons, which is 4.5 litres and not US gals, which is 3.85 litres, so I will show a much lower gph.

At about 10K feet the MP is under 20" which is under 55% power. I still clocked 160kts depending on winds aloft. At that power setting it's no wonder that my figures differ from a 75% setting at low altitudes.

Where can one see your video. I have fond memories of a friend who owned a Mooney with the hand operated gear lever. Fastest retraction in the sky.

Sorry it took me so long to get back to you. I didn't notice that you had replied to my post cause I didn't get the normal email. If you haven't found it already and are still interested you just click on my profile name and watch it on my profile.

Oh, and Twin Comanche's have IO-320's if I'm not mistaken. 160 hp (feel free to correct me if I'm wrong here). The L360 has, as the 360 suggests, Lycoming IO-360M1A's.

You are right it has 320's not 360's. I was mistaken and already apologized to Paul for the mistake.

It's fine man, I was just trying to point out that perhaps the DA42 would burn a bit more than a Twin Comanche, although I'm sure that if you throttled back quite a ways that you could get 5.4 gph per engine and by nature of the newer, most likely more efficient design, you could probably get about the same speed even though you were in a heavier aircraft (I believe the Twin Comanche is 3725 gross and that the L360 version of the Twin Star is 3968).