Hello Folk,
The following is a series of raw conversations regarding TCFG members' thoughts/experience with flying/owning the Model 680F Aero Commander. These conversations are sourced from the TCFG Chatlist in the early 2000's and are strictly the opinions of members at the time.
While I am sure the experiences discussed are still as relevant in 2015, it should be noted that some key members featured have since passed out of Commander ownership.
Enjoy!
Cheers
Russell
VH-CAU
560E s/n 726
680F
I have just recently added my email address to your group.
In response to discussion about actual operational experience, I offer the
following: I have owned a 680F now for 2 years, which I operate out of San
Luis Obispo, CA. I fly primarily for busines, approx 100 hours per year,
with typical legs about 1 hour. Longest flight has been to Oshkosh and
back last year. Average fuel burn was 52 gal per hour (book value is
closer to 40 gph) at 70% power (30" & 2600 rpm, leaned to 190 C cht). Any
suggestions to lower fuel consumption would be appreciated. The high fuel
burn, however, is compensated by superb performance - 2700 lb usuful load
(8000 lb gross), 1000 fpm climb at 140 kph indicated at gross wt, with 190
kph true airspeed at the above power setting. Engines are Lyc. IGSO-540's.
Randy Dettmer.
----- Original Message -----
Randy,
Thank you so much for posting your 680F experience!
As for lowering your fuel burn, keep it up there. I used to advocate 20
degrees lean of peak on the IGSO-540s, per Lycoming's operating tips.
However, after many discussions with Suburban Air Freight (they used to
operate a fleet of 680-FLs) I have come to realize that the valve guides and
other components depend on lead for lubrication and that lead content it not
available in modern avgas. Run rich.
We're getting some good data rolling in. Keep it coming!
Hi Randy:
I too own a 680F. Superb machine!!!. That is the typical set out for
that fuel burn, although sometimes I do 30,5 at 2650, and ussually I take
it to about 20-23GPH on each, meaning just a bit under 50. CHT abot 200-210
I fly that craft with someone who use to fly one like it for over 20
years. He has taught me to TO at 45-46MP, gear up, falps up, the go down to
40@3000rpm and just cruise at 500fpm bellow 7000 then on to 700fpm over 7k,
up to 10 or 11000 msl. This will keep you cruising fast at indicated 180MPH
constantly, reducing your flight. but it avgs about 50GPH on an one hour
leg.
Right now I have to go above 75% beacuse i have just overhauled my
engines. Now he guzzles fuel. Avg 58-62 GPH but you fly at 195 MPH
indicated or about 200knots true.
Good information from you all regarding fuel burn.
A couple of additional thoughts regarding my 680F... I typically TO at 45"
and 3400 rpm, reduce to 3200 rpm after lift-off, cruise climb at 40" and
3000 rpm at 140 KIAS to 10 or 11K (1000 FPM) Thanks again.
