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Old Toys

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I am having a lot of trouble deciding on the 4 vs 8.
I don't need the plane for cross country. I fly only for enjoyment. I want to be able to take friends and family for spirited rides. Nothing real aggressive but I would like to be able to do loops and rolls. I don't have many friends under 200 pounds. :D I'm not worried about the snug fit as long as I'm not tail heavy.
So my question is what would be the heaviest person you would put in the rear seat under those conditions?
Thanks, Tim
 
I'm heavy

Tim,
I weigh 220lbs, + clothed and have ridden in the back of a 150 HP RV4. We did rolls, etc. and it was fine. However, on the other hand, I was building a -4 and have two boys that each weigh 250-300lbs and knew that they would NEVER get to ride in it, so I sold the -4 and am building a -7. Still love the 4 though. Sold the project to someone on the field and still may get to fly it one day. :D
YMMV.
 
Hi Tim,

I have ridden in the back of my Dad?s -4 with a wood prop and O-320 up front, I am 235lb, Dad said it was fine, we did rolls and wing overs.

I have had a 6?4? 250 pounder in the back of my -4, yes I did do a wait & balance before I went and it was fine but at the rear of the CG, we did no acro loaded this way and yes we where over Van?s gross.

It all depends on the RV-4 you are looking to buy, they all have a different wait & balance so you just have to run the numbers on the plane you?re looking at, then decide. Also using Van?s CG limits is a must!!!! The plane is truly at its rear limit at the rear of its CG envelope and at the rear it is not for acro! As for the max gross, I think the service history of the -4 proves Van well under estimated the max gross, mine has seen 1750lb regularly, basically the max weight is more limited buy the CG in this plane then the structure. I did the math and I think if I am correct Jon Johansson was taking off at over 2000lb maybe 2100lb on his round the world flights in the -4.

As far as acro goes, the -4 has a 1375lb gross not including fuel in the wings good for 6G. 1375 times 6 = 8250lb of force. So let?s see what it looks like with two on board.

My -4, 1077lb + pilot 235 + passenger 200 = 1512lbs, 8250lb divided buy 1512 = 5.45 G. Looks like I lost a half a G loading for acro, since I never pull more then 3 G doing any acro and am well practiced I am happy doing acro loaded in this way.

So when you look at a plane to buy check the W & B and do the math.

Also this probably goes for the -8 as well as for the -4, whichever one you get, don?t go out and fly for ten hours solo then through in a passenger and baggage to the aft limit and go, the -4 for sure is a very different handling plane loaded aft, recommend you work your way from the front of the CG to the rear so you don?t get a big surprise!

Russ
 
The 8 can tolerate very heavy back seaters

The RV-8 is hard to load in such a way as to get to the aft c.g. limit. Most all the loadings I've tried on the W&B, you get to gross before you get to aft limit.

This is even more likely true if you are adhering to the aerobatic gross weight, which is 1600 lb instead of 1800. With a heavy back seater, you would have to off-load some fuel, but you won't have an aft c.g. problem.

Example: 1120 empty + 200 front + 200 back + 80 fuel (13 gal). Thats about 20-30 minutes of high-power flying plus a 30 minute reserve. Can you make someone sick in 20 minutes? :D

at full gross of 1800 lb, 280 lb fuel is an easy 4 hrs + reserve.

The 8 is really roomy and cumfy in the back.
 
scsmith said:
The RV-8 is hard to load in such a way as to get to the aft c.g. limit. Most all the loadings I've tried on the W&B, you get to gross before you get to aft limit.

This is even more likely true if you are adhering to the aerobatic gross weight, which is 1600 lb instead of 1800. With a heavy back seater, you would have to off-load some fuel, but you won't have an aft c.g. problem.

Example: 1120 empty + 200 front + 200 back + 80 fuel (13 gal). Thats about 20-30 minutes of high-power flying plus a 30 minute reserve. Can you make someone sick in 20 minutes? :D

at full gross of 1800 lb, 280 lb fuel is an easy 4 hrs + reserve.

The 8 is really roomy and cumfy in the back.
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Hey Steve,

Your math is completely correct,and it is very hard to put enough weight in the back to load out of the aft end of the envelope. However.....(and you just knew there was a however, right?)...I seriously doubt that you will be interested in Acro if you are loaded THAT far aft. The airplane is positively spooky when you approach the aft limit - at least in my book (and a number of other experienced -8 drivers I have talked to)!

I won't do much if any acro with a passenegr, unless they are pretty light. Remember - to be legal, they need a parachute as well, and that weighs a bit too...

Paul
 
Old Toys said:
I want to be able to take friends and family for spirited rides. .. Tim
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Tim, I have just passed 50 hours and 70 landings with a -4. It is an absolute delight, but I am still a beginner with it. A few comments:

1) The -4 has a 1375lb gross for aeros.
2) While it the easiest aircraft to land solo, I am still finding it challenging 2 up. Many folk put a limit on the rear seat. For now, mine is 160lbs. Others use a heavier limit.
3) There is a post today which captures just a shadow of what the -4 is about. read here. Its a pale shadow though. You will have to go fly one.

My suggestion would be to buy a -4 and tell your friends to go the gym!
 
Thanks guys for the reply's.
It sounds like I should stray away from exceeding 200 pounds in the back seat. I am going to look at a 4 with a 360 and C/S it should allow for a little more weight in the rear seat.
 
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I've done quite a bit of acro with 200-225 lbs. in the back seat of my 4, and it is a lot different. Know your airplane and your own limitations. It is quite different from solo. But can be done.
 
Max weight?

So my question is what would be the heaviest person you would put in the rear seat under those conditions?
Thanks, Tim


Tim,
In 1400 RV4 and 400 Rocket hours I have the following answer: Cute girls less than 110 lbs who like to travel light, fly upside down and camp in the back country, all others need to buy their own airplane, or as Steve stated, hit the gym...:)

Smokey
HR2

PS: I kept my RV4 max back seat limit at 200 lbs total aft of the Roll bar for flight, aerobatics solo only...in the Rocket that number is 300 lbs
 
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