Twin Comanche Weight and Balance...

[redbelliedjet]

Hello everyone,

I'm still doing my homework for my aircraft purchase.

I was curious if anyone might have the weight and balance charts for the TC?

I bought the Owners Handbook, but found no charts and graphs for weight and balance calcs. I have the weight info, but I am trying to find out if the aircraft is easily loaded out of forward or aft CG. If I buy one, I am looking to fly with my wife and four fairy small kids with a little luggage. Would this tend to throw a TC out of aft CG? Would the aircraft tend to be out of forward CG if I was flying alone?

Thanks for any info!

Cheers,

Dan

[Zach Grant L1011jock]

Dan,

All Comanches have very liberal CG envelopes, and they are not terribly critical if you get near the edges or get outside a little either. Most twins are very difficult to load out aft. You can get them out forward, especially the turbo B/C/39's with the forward battery and the tip tanks. Solo shouldn't be a problem staying in the envelope, but full fuel and two folks up front with no bags will be on the forward limit, if not significantly forward of the front limit. The plane still flys fine in this condition, it just has less ability to flare, but most do the chop and plop anyway...Adding just 50# of whatever in the luggage compartment fixes all the ills. The plane does fly better towards rear CG.

-Zach

[N3322G]

Dan,

Ditto what Zach said and I'll add that decades ago we looked at buying a Beech when the Twin lived 8000 miles away - either a Debonair or a Bonanza and found that at the end of the flight there was a significant problem with CG potentially being aft. I didn't like that risk and looked elsewhere.

After 40 years of flying the Twin (normally aspirated), we can get a forward or aft CG, we just have to work at it ie, heavy tool box aft and luggage with 1 hour of fuel on board or lots of fuel and nothing aft.

We still run weight and balance calculations if we are carrying something unfamiliar to make sure we don't have a problem at take-off or landing.

The envelope is on page 6-12 of the Pilot Operating Handbook (POH) Figure 6-1 for the PA39. This can be purchased from http://www.webcoaircraft.com/ I call rather than use the website. The POH I have at home is bound and has 12 pages in the weight and balance section or I'd volunteer to fax it to you.

Great to see you are so thorough in your research.

[Jay]

Good scoop from Zach and Pat. I'd add just a couple of points.

As Zach alluded, different models of Twinkie have significantly different configurations and thus different empty CG's. Battery forward or aft, built in O2 or not, turbo or not, tip tanks or not, nacelle tanks or not, avionics forward or aft and how much, etc.

Most of these airplanes have been modified to one extent or another over the years, so "standard" starting moment and empty weight numbers are pretty meaningless. You really need to look at each specific aircraft.

In my airplane if it's just me or one passenger and light bags I put 75 lbs of lead shot in the baggage compartment. Others use water, oil, tools or whatever to get the same W&B effect. If I have folks in the back seat or lots of bags, I leave the ballast in the hangar.

Much as I hate to be burning fuel hauling ballast around, besides resolving real or potential CG issues moving the CG aft makes those ego pleasing smooth landings a lot easier.

Too long to post here, but I once found myself flying a an airplane with the CG significantly out of the back side of the envelope. It was NOT a good thing, a very stable airplane was suddenly unbelievable squirrelly.

Jay

[redbelliedjet]

Thanks all,

It sounds like the Twinkie is pretty accomodating as far as the CG is concerned. I appreciate all of the input in my quest for info! Other than a couple of inconvenient AD's and SB's, it appears that the airplane really doesn't have any bad habits and will work well for my needs.

Once again, thank you all for the help.

Cheers,
Dan

[N8632Y]