Forum

Notifications
Clear all

This Forum is a place for Piper Comanche pilots to communicate and discuss technical issues

If you join or reset a password, please check your Spam Email box for emails from Admin at ComancheTechTalk.com

Please put your questions on the forum as well so everyone can read and respond. Someone else might be having similar questions.

All questions or topics on the Forums automatically get sent to the Tech team as well.

TIP TANKS FOR PA-24-250

1 Posts
1 Users
0 Reactions
1,699 Views
Admin
Joined: 5 years ago
Posts: 1162
Topic starter  

TIP TANKS FOR PA-24-250

Postby bartsch » Wed Jan 19, 2011 4:56 pm

I am installing tip tanks on my pa-24, I was wondering where I should go to research how the plane will react (Va, crosswinds, ground effect, etc) with the new tanks, any suggestions?
bartsch
ICS member
ICS member
 
Posts: 1
Joined: Fri Oct 01, 2010 8:29 pm

Re: TIP TANKS FOR PA-24-250

Postby Kristin Winter » Thu Jan 20, 2011 6:08 am

Not meaning to be flip, but I would suggest the traffic pattern. You may not notice the difference in handling. You might notice a bit more airspeed at higher altitude.
Kristin
User avatar
Kristin Winter
ICS member
ICS member
 
Posts: 1299
Joined: Tue Aug 09, 2005 5:21 pm
Location: Northern California

Re: TIP TANKS FOR PA-24-250

Postby Hank Spellman » Thu Jan 20, 2011 10:42 am

I have had tip tanks on my 250 for years. The only thing I have noticed is a very slight increase in IAS at and above 8000 feet.

I would also suggest that you also strongly consider an Aero-Trim electric aileron trim tab ( http://www.aeroresourcesinc.com/store_/ ). Price is $795. Installation is fairly simple. The electric trim allows you to trim out a heavy wing for coordinated flight so you don't have to hold a constant pressure on the yoke, or, if you have an autopilot, it saves the servos running all the time to stop the roll. An imbalance in the fuel quantity in the tip tanks can result in quite a hand full. Trying to burn from both tips at the same time does not work (impossible on the models originally equipped with four tanks, but possible on the two tank models). What happens is that the fuel will transfer through the selector valves and down into the lower (in altitude) tank, making it even heavier and even more below the level of the other tank. Eventually, the lower tank will overflow and the fuel will go overboard.

This particular arrangement can be used to transfer fuel ON THE GROUND ONLY from one tip to the opposite main by selecting one tip and the opposite main. The fuel will run out of the tip, through the selector valves, and into the opposite main. This trick can be used to get an absolutely full main tank. The tips then have to be topped off again. It will only work on the early model 250's (1960 and earlier). It will not work on the later singles because the plumbing for the tank selection is different.

I hope this helps.

Hank

User avatar
Hank Spellman
Moderator
Moderator
 
Posts: 120
Joined: Thu Jan 20, 2000 3:13 am
Location: Lincoln, IL

Re: TIP TANKS FOR PA-24-250

Postby Jay » Thu Jan 20, 2011 4:55 pm

Good on you, that's really the best mod for Comanches that there is. I honestly don't ever even think about differences in handling with full tanks versus empty. The slight increase in speed is real, and the extra range and W&B flexibility is great.

Jay

Jay
PA 30 N7702Y
User avatar
Jay
ICS member
ICS member
 
Posts: 473
Joined: Tue Sep 30, 2003 10:59 pm
Location: Portland, Oregon
  •  

Re: TIP TANKS FOR PA-24-250

Postby David Pyle » Thu Jan 20, 2011 8:12 pm

Hank Spellman is far better looking than his picture.

Looks like he is "tipping" more than avgas.

713 464 6717
dap8@comcast.net
David Pyle
ICS member
ICS member
 
Posts: 372
Joined: Sat Nov 01, 2003 10:33 pm
Location: Houston
  •  

Re: TIP TANKS FOR PA-24-250

Postby Chief » Thu Jan 20, 2011 10:32 pm

Brent,

Our Comanche 250 has tips. I've had it for 2 years. Love them. It definitely helps in a crosswind, always plan more fuel in your upwind tank, it will be heavier and it helps dip into wind. DO BE CAREFUL with an imbalance if you don't burn tips at same rate, you will get a (hopefully noticable) wing dip. Very noticable in the day and VFR. Night/IFR, pay attention!

Not sure about crossfeeding, never tried, probably never will, not good to run tips dry per the manufacturer. I'm afraid I'd run them dry and get air in lines.

I always keep tips full of fuel. Best speed mod made, you don't have to land and refuel.

One last thing, your Vna speed changes, it drops, so be careful to slow down when turbulence or manuevers require it. It is in the Osborne notes!

But I highly recommend the upgrade.

User avatar
Chief
ICS member
ICS member
 
Posts: 41
Joined: Sun Nov 09, 2008 11:01 pm
Location: K9A4

Re: TIP TANKS FOR PA-24-250

Postby Zach Grant L1011jock » Thu Jan 20, 2011 11:26 pm

Brent,
You will find more roll inertia with the tip tanks installed and full, vs a stock airplane. This helps in turbulance as there is less displacement from vertical gusts, but it will also cause slightly less responsive handling, as well as additional inertia once the roll does develop. One of the big errors people make is at slow speed, setting up a PIO in roll (310's are especially bad for this). Not doing this is simple. Don't make control inputs you don't want the aircraft to follow! Realistically on a Comanche, you will not notice any difference with them installed/empty, and you will only notice a real difference between empty and full if you are looking for it. Fly the plane, make it do what you want it to do.
-Zach
"Keep it above 5 feet and don't do nuthin dumb!"
User avatar
Zach Grant L1011jock
Technical Advisor
 
Posts: 1404
Joined: Mon Mar 22, 2004 4:35 pm
Location: Indianapolis KEYE

   
Quote
Share: