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-   -   Any first hand knowledge of RV7A 200# over gross? (https://vansairforce.net/community/showthread.php?t=171838)

hevansrv7a 05-25-2019 01:05 PM

Any first hand knowledge of RV7A 200# over gross?
 
I have been consulting with another pilot who is considering putting in extra fuel for a very long over-water flight in a 7A. He would need to fly 200 pounds over gross weight. Naturally, I'm not encouraging that.

However, I'm trying to help him find out what others may know about doing that.

Any info you can supply would be helpful.

Also, any info on the advantages or disadvantages of an extra tank in the area of the right seat vs. adding tip tanks?

H

Discus2b 05-25-2019 02:57 PM

I ferried a Casa 212 from Hawaii under the direction of a highly experienced ferry/Hawaiian Airline pilot. Under his tutelage, he informed me that with careful w&b checking and careful pilotage, aircraft will fly fine at 100% over gross.
And we were just about there at takeoff from Hawaii Honolulu Airport.
It took 10,000? of runway to ease off and would not climb above 2500? for 3 hrs, but it flew.
W&B
New Tires over inflated to round.
Insurance investigation....may not cover at takeoff, but begins at gross weight.
Performance....runway, density altitude, obstacles, etc.
Over Water contingency plans.
Have Vans give a wag on struts weight limits. How many Gs during the drop test. My bet over 2.
200# over wouldn?t attract my attention, its already been done.
Oh.....strap it down, accelerate sssllloooowwwlllyyyy.

R

R

Capt 05-26-2019 12:44 AM

Obviously any type of operation outside of its intended use is done so at yr own risk, The above post covers most of it. A large proportion of A/C take off overweight everyday around the world including Airliners, some unintentional some not so. Disclaimer in place now.....as long as the A/C is in balance and has enuf power to gain height above the stall speed then they will fly, you are now in test pilot territory though and you do so of course at your own peril�� Safe flying��

Chris7 05-26-2019 04:40 AM

Having personally ferried many aircraft (all overweight and legal), the best thing to do is talk to Van's. Being a homebuilt I doubt they would issue anything to say it's ok but at least talking to them is a good idea. The FAA may issue a small percentage over gross but again depends.
Then talk to the insurance company about it, if they won't cover it then it's a no go. I doubt he would be willing to risk it all with no insurance? Most insurance companies will cover it if there is paperwork to approve the overweight, maybe with an increased premium depending on where the flight is.

Now for the flying, 200# it most likely won't fly any different.
Definitely a tank inside is better because the load on the tips probably hasn't been tested for tip tanks.
Make 100% sure its within CofG, aircraft get very squirly if the CofG is aft (or forward even worse sometimes).

If you want to PM me, I'm happy to go into more depth because I've seen too many make bad decisions even when approved for this type of operation so my advice and help is free to prevent this.

Disclaimer, although I've done this many times (too many) its a forever learning experience so I can't cover all the needs of every flight.

snopercod 05-26-2019 05:51 AM

In general, the stall speed will be ~54 instead of 51 (sqrt 2000/1800). Takeoff distance will be longer, climb rate will be lower.

hevansrv7a 05-26-2019 02:13 PM

The question has been answered. THANKS.
 
The pilot for whom I asked the question has obtained the answers he needed. Thanks for the help.

h

FutureRV 05-28-2019 12:19 AM

Quote:

Originally Posted by Discus2b (Post 1348797)
I ferried a Casa 212 from Hawaii under the direction of a highly experienced ferry/Hawaiian Airline pilot. Under his tutelage, he informed me that with careful w&b checking and careful pilotage, aircraft will fly fine at 100% over gross.
And we were just about there at takeoff from Hawaii Honolulu Airport.
It took 10,000? of runway to ease off and would not climb above 2500? for 3 hrs, but it flew.
W&B
New Tires over inflated to round.
Insurance investigation....may not cover at takeoff, but begins at gross weight.
Performance....runway, density altitude, obstacles, etc.
Over Water contingency plans.
Have Vans give a wag on struts weight limits. How many Gs during the drop test. My bet over 2.
200# over wouldn?t attract my attention, its already been done.
Oh.....strap it down, accelerate sssllloooowwwlllyyyy.

R

R

Was that around 1990. I ask because a Casa 212 being ferried from Tonga broke down in Pago Pago. I flew a test flight witn a Hawaiian Pilot in the aircraft ferry business. If so, small world.

Discus2b 05-28-2019 05:46 AM

Quote:

Originally Posted by FutureRV (Post 1349215)
Was that around 1990. I ask because a Casa 212 being ferried from Tonga broke down in Pago Pago. I flew a test flight witn a Hawaiian Pilot in the aircraft ferry business. If so, small world.

No, around ?85 as I?m not home to check the log books. 1990 I was flying C-130s. Ahhhh, memories. What little I can remember.

R

sailvi767 05-28-2019 06:02 AM

You might try and track down the owner of N577DL.
George

http://www.vansairforce.com/communit...ad.php?t=83504

scsmith 05-28-2019 11:32 AM

One of the issues for flight at weights above recommended gross weight is structural margin, primarily due to gust loads. You can impose your own maneuver load limit in proportion to the weight addition to preserve margin, but you can't control gusts, except by choosing your flying environment.

This is one thing where tip tanks are better than a fuselage tank. You get "inertia relief" from the added weight, especially at the tip, that reduces the gust loads pretty dramatically.

I would still recommend a structural analysis under Part 23 gust load criteria as part of the design process. But it is not too difficult.

Sue 05-30-2019 03:29 PM

Gross weight
 
In Alaska 15% over gross is not a problem?

Sue 05-30-2019 03:32 PM

Gross weight
 
Sorry FAR 91.323


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