VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics


Go Back   VAF Forums > Model Specific > RV-6/6A
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
  #31  
Old 04-28-2018, 04:15 PM
Turbo69bird Turbo69bird is offline
 
Join Date: Jun 2013
Location: CT
Posts: 179
Default

Quote:
Originally Posted by Sam Buchanan View Post
You took off at a few pounds over gross for the RV-6 (~1680 lbs). I would consider 700 ft/min at that weight with an O-320 turning a cruise prop to be excellent preformance. You have a good airplane.

My weight and balance lbs

Man thatís about useless at 1680most of my buddyís are 230 240 lbs.

My plane as I recall was 1150 empty weight but Iíll check on that. Itís got full interior and insulation behind it so I assume its heavy. Iím planning to re-scale it since I just did vinyl wrap over my paint. I did wet sand it a bit to shave some weight off the paint, but wanted the corrosion protection.

Problem is at the weight of most people I know, if I pull fuel out it gets and aft CG.so I do a dance beteween gross and aft cg. I also carry a hand held radio, two I pads a back up battery pack, my cell phone, my cover, chocks etc But I do have the carpet out 🤔

However (I feel) it still, doesnít climb great within me alone in it. I lol get some numbers with me alone and half fuel. For comparison. It is a nice airplane just doesnít climb like others. Iíve had people comment on it after most takeoff and landings.

I have two friends with RV7s and they climb like helicopters. As does the archer I fly.
__________________
Proud owner of 925RV
Special Thanks to Fred Stucklen


While I'm not a builder if I happen to give advice , I will not be responsible for damage to equipment, your ego, parts, world wide power outages, spontaneously generated black holes, planetary disruptions, or personal injury that may result from the use of this advice.
Reply With Quote
  #32  
Old 04-28-2018, 04:20 PM
RV8JD's Avatar
RV8JD RV8JD is offline
 
Join Date: Jan 2005
Posts: 884
Default

Quote:
Originally Posted by Turbo69bird View Post
... most of my buddy’s are 230 240 lbs.

Problem is at the weight of most people I know, ...
Isn't that why God (Ahem ... I mean Van's) designed the RV-14?
__________________
Carl N.
Arlington, WA (KAWO)
RV-8, 405 Tach Hours
(Pic 1),(Pic 2)
- Out with the Old, In with the New
(Pic)
RV-8, 1938 Tach Hours (Pic 1),(Pic 2) - Sold

GlasflŁgel Standard Libelle 201B, N564NS - Sold
Rolladen-Schneider LS1-f, N61MP - No longer owned

Last edited by RV8JD : 04-28-2018 at 04:22 PM.
Reply With Quote
  #33  
Old 04-28-2018, 05:39 PM
Sam Buchanan's Avatar
Sam Buchanan Sam Buchanan is offline
been here awhile
 
Join Date: Dec 2004
Location: North Alabama
Posts: 3,795
Default

Quote:
Originally Posted by Turbo69bird View Post
My weight and balance lbs

Man that’s about useless at 1680most of my buddy’s are 230 240 lbs.

My plane as I recall was 1150 empty weight but I’ll check on that. It’s got full interior and insulation behind it so I assume its heavy. I’m planning to re-scale it since I just did vinyl wrap over my paint. I did wet sand it a bit to shave some weight off the paint, but wanted the corrosion protection.

Problem is at the weight of most people I know, if I pull fuel out it gets and aft CG.so I do a dance beteween gross and aft cg. I also carry a hand held radio, two I pads a back up battery pack, my cell phone, my cover, chocks etc But I do have the carpet out ��

However (I feel) it still, doesn’t climb great within me alone in it. I lol get some numbers with me alone and half fuel. For comparison. It is a nice airplane just doesn’t climb like others. I’ve had people comment on it after most takeoff and landings.

I have two friends with RV7s and they climb like helicopters. As does the archer I fly.
You have a very heavy RV-6A (my RV-6 hit the scales at 1010 lbs...painted). Guess your choice is to be satisfied with the performance you have or get a different airplane.....me thinks the O-320 and cruise prop are doing about all they can.
__________________
Sam Buchanan
1999 RV-6
1918 Fokker D.VII replica

Last edited by Sam Buchanan : 04-28-2018 at 05:45 PM.
Reply With Quote
  #34  
Old 04-28-2018, 07:07 PM
titanhank's Avatar
titanhank titanhank is offline
 
Join Date: Aug 2007
Location: Friendswood, Tx
Posts: 218
Default

I did a max weight takeoff with my 160hp 0-320 rv 6 and catto 3 blade 67x70Ē prop a while back. The takeoff weight was 1730 lbs. This was 1064 empty weight, 245lbs pilot, 240lbs pax and 30 gallons of fuel. The density altitude was 1500ft as reported by asos and temp was 31deg C with relative humidity of 85%. We used 1 notch of flaps to approx 300 ft and WOT showed 2200 rpms. This gave us an inital climb rate of 600-700 fpm at 80-90 mph to clear the trees on a 4000 ft concrete runway. After reaching 300 ft at about mid field, flaps were retracted and established a 110mph cruise climb at 2450 rpms with 700-800 fpm climb rate. It flew very much like a cessna 172 departure profile at high weights and temps. This weight and balance solution gave us 8 gallons to burn without the aft cg limit being exceeded. We climbed to 2000ft and did a series of stick pull phugoid manuevers to check the pitch stability. The airplane respond with slow, but positive stability all the way to the aft cg limit. It did become slightly more pitch sensitive, but nothing scarey. I would not exceed the aft cg limit under any circumstances after this test. I used 5 mph higher speeds in the pattern, 95mph downwind and 85mph on final. It three point landed very nicely. The landing weight was 1675lbs with a landing cg of 76.79". Now that the new panel is installed, it is time to start planning a whirlwind c/s prop upgrade. It never ends. 😜
__________________
Rv-6
0-320/160hp
Dual pmags
Catto 3-blade gen 3
Smoke system
Glass panel
Autopilot
Flightline Interior
Almost rv14 seat mod
Reply With Quote
  #35  
Old 04-30-2018, 02:30 PM
Turbo69bird Turbo69bird is offline
 
Join Date: Jun 2013
Location: CT
Posts: 179
Default

I appreciate all the answers, Iím still going to do some more testing and most importantly scale my plane to see exactly where it starts out in the weight end of things.

Thought about repitching the sensenich but if I find out itís somethung else sticking exhaust valve , cam lobe etc then Iíll be stuck with a prop thatís not optimal. And it might just simply be that the ole girl has gotten porky over the years, lord knows the pilot and passengers have .lol.

The more o hear others numbers the more it seems fairly normal. Weíll see and Iíll update the thread.
__________________
Proud owner of 925RV
Special Thanks to Fred Stucklen


While I'm not a builder if I happen to give advice , I will not be responsible for damage to equipment, your ego, parts, world wide power outages, spontaneously generated black holes, planetary disruptions, or personal injury that may result from the use of this advice.
Reply With Quote
  #36  
Old 05-03-2018, 12:01 PM
smokyray's Avatar
smokyray smokyray is offline
 
Join Date: Jan 2005
Location: TX32
Posts: 1,734
Default By the numbers...

Jeff,

I recommend you do as you planned: a good W&B, compression check on the engine.
Additionally:
1.Try leaning slightly on takeoff roll if you haven't already.
2.If you're running mags, REM-37BY plugs are a bit hotter and I gained 50 static RPM with them on my 0-320 powered RV4. (E.I will gain you almost 100RPM)
3.Get rid of any excess weight you can (heavy battery, interior,insulation, starter, alt, unneeded junk onboard you mentioned, it all adds up) Mount the lighter battery on the firewall to help CG.
4.Consider selling rather than re-pitching your Sensy metal and purchasing a Catto or similar composite or wood climb prop. They reduce your EW, far better climb rate and smooth. (Of all Nine props I've tested over 25 years, The Sensy metal is my least favorite, 2600RPM restriction, no acro etc.)
5.Consider Electronic ignition if you haven't already as it adds performance.
6.Fly at reduced fuel loads, that helps too especially if your passenger exceeds 200lbs. *I used to have a rule in my RV4 to carry no passenger above 200lbs for CG reasons. (consider girl passengers instead...)


The lighter they are, the better they fly....
V/R
Smokey

PS:My RVX is basically an RV6 fuselage mated to RV4 wings and tail. It weighs 945lbs empty with an 0-360J2A, (180HP de-rated Robinson R22 engine) dual E.I., 2 blade Catto lightweight starter/alt/batt 170lb Pilot.
(All my local flying is done at less than 1/2 fuel as I perform Acro and the airplane simply flies better.)
By the numbers:
Solo climb rate with half fuel 100KIAS is 1500FPM on a 95F TX summer day.Full fuel with a 120lb pax/25lbs baggage is 1000FPM (add 500FPM to both for winter temp climb numbers

PSS: We visit Telluride CO (9070' elev) every summer and I use my summer takeoff numbers there as a worst case performance scenario.
2 on board, 1/2 fuel and 25lbs of bags (I never take off full fuel/pax/bags in the mountains) 75F static RPM is 2050, takeoff 2100 leaned out and climb at 100KTS is 2250@500FPM.

Last edited by smokyray : 05-03-2018 at 04:05 PM.
Reply With Quote
  #37  
Old 05-04-2018, 10:04 PM
Turbo69bird Turbo69bird is offline
 
Join Date: Jun 2013
Location: CT
Posts: 179
Default

Quote:
Originally Posted by smokyray View Post
Jeff,

I recommend you do as you planned: a good W&B, compression check on the engine.
Additionally:
1.Try leaning slightly on takeoff roll if you haven't already.
2.If you're running mags, REM-37BY plugs are a bit hotter and I gained 50 static RPM with them on my 0-320 powered RV4. (E.I will gain you almost 100RPM)
3.Get rid of any excess weight you can (heavy battery, interior,insulation, starter, alt, unneeded junk onboard you mentioned, it all adds up) Mount the lighter battery on the firewall to help CG.
4.Consider selling rather than re-pitching your Sensy metal and purchasing a Catto or similar composite or wood climb prop. They reduce your EW, far better climb rate and smooth. (Of all Nine props I've tested over 25 years, The Sensy metal is my least favorite, 2600RPM restriction, no acro etc.)
5.Consider Electronic ignition if you haven't already as it adds performance.
6.Fly at reduced fuel loads, that helps too especially if your passenger exceeds 200lbs. *I used to have a rule in my RV4 to carry no passenger above 200lbs for CG reasons. (consider girl passengers instead...)


The lighter they are, the better they fly....
V/R
Smokey

PS:My RVX is basically an RV6 fuselage mated to RV4 wings and tail. It weighs 945lbs empty with an 0-360J2A, (180HP de-rated Robinson R22 engine) dual E.I., 2 blade Catto lightweight starter/alt/batt 170lb Pilot.
(All my local flying is done at less than 1/2 fuel as I perform Acro and the airplane simply flies better.)
By the numbers:
Solo climb rate with half fuel 100KIAS is 1500FPM on a 95F TX summer day.Full fuel with a 120lb pax/25lbs baggage is 1000FPM (add 500FPM to both for winter temp climb numbers

PSS: We visit Telluride CO (9070' elev) every summer and I use my summer takeoff numbers there as a worst case performance scenario.
2 on board, 1/2 fuel and 25lbs of bags (I never take off full fuel/pax/bags in the mountains) 75F static RPM is 2050, takeoff 2100 leaned out and climb at 100KTS is 2250@500FPM.


Thanks so much for the detailed info. That goes for everyone who replied. Iím hoping to scale in next week. One reason I donít fly with reduced fuel loads is the CG and thatís also the reason I havenít switched to a light prop.

Hereís the airplane for those of you whoíd like to see it.
Www.vansrv6.com

My battery is fairly light and mounted on the floor up against the firewall. Sealed gel type.
I do t think I even know anyone under 200 lbs except girls. Lol. The wife frowns upon too many of those pax though. Lmao
I donít know that it really climbs out much better with me alone in it. Honestly, I know it floats more on landing but in take off I donít really notice that much. Difference.
__________________
Proud owner of 925RV
Special Thanks to Fred Stucklen


While I'm not a builder if I happen to give advice , I will not be responsible for damage to equipment, your ego, parts, world wide power outages, spontaneously generated black holes, planetary disruptions, or personal injury that may result from the use of this advice.
Reply With Quote
  #38  
Old 05-05-2018, 07:21 AM
Sam Buchanan's Avatar
Sam Buchanan Sam Buchanan is offline
been here awhile
 
Join Date: Dec 2004
Location: North Alabama
Posts: 3,795
Default

One unfortunate aspect of this situation is that you have not experienced the real RV performance envelope. Because you are always flying heavy, your plane never performs as Van intended. Excess weight affects all corners of the envelope, not just climb.

A flight in a light RV would be an eye opener.
__________________
Sam Buchanan
1999 RV-6
1918 Fokker D.VII replica
Reply With Quote
  #39  
Old 05-05-2018, 04:55 PM
Turbo69bird Turbo69bird is offline
 
Join Date: Jun 2013
Location: CT
Posts: 179
Default

Didnít look at much today just took my kid up for a flight but did notice that with her light weight in it pitched for 100 mph rage of climb was 1000 ft per minute. Didnít feel like it got off the ground much quicker though. Maybe slightly but not significant.

Didnít check my static rpm I will next time out though. Had a very short window and the focus was on taking the kid for a,ride.
__________________
Proud owner of 925RV
Special Thanks to Fred Stucklen


While I'm not a builder if I happen to give advice , I will not be responsible for damage to equipment, your ego, parts, world wide power outages, spontaneously generated black holes, planetary disruptions, or personal injury that may result from the use of this advice.
Reply With Quote
  #40  
Old 05-31-2018, 10:14 PM
Plumbmaster's Avatar
Plumbmaster Plumbmaster is offline
 
Join Date: Aug 2017
Location: Concord, CA
Posts: 30
Smile Ground Roll And Climb Out RPM

Sounds pretty much like a cruise prop to me. Thing is and correct me if I'm wrong, you can re-pitch the prop to get a higher rpm on take off. Around these parts of the woods that's around $1200. Or you can get a Cato prop which seems to act like a variable pitch prop-high rpm on take off followed by cruise speeds in the 150 knot range. They're reasonably affordable at @ $3000.
High compression pistons will help generate more power with your prop as is.
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 10:49 PM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.