What's new
Van's Air Force

The definitive Van's Aircraft support community! Buying, building or flying an RV? Join our exclusive family of mentors and enthusiasts!

RV-10 Heavy Weight Max Range TAS Fuel Flow

R

RV10Kiwi

I'm New Here
Hi everyone,
I am a newbie to the website. I am considering buying a RV-10 for a round the world adventure. As part of the research, I am evaluating several aircraft ...my preferred favourite is the RV-10 but I'm struggling to find any RV-10 heavy weight (MTOW) TAS Fuel Flows at LOP and how it changes as you burn down to lighter weights. I'd also love to hear from anyone who has ferried one with Turtle tanks or similar and experienced any aft CG issues.
Thanks in advance !!
 
Suggest you reach out to @Paddy. He flew his RV-10 across the North Atlantic to Ireland and back. He built a very nice ferry tank and fuel distribution setup.
 
Out of curiosity, what are your longest anticpated legs? I've run the range numbers a few times and contemplated how to add fuel capacity for truly long range legs (though it is just a mental exercise in my case.)
 
Most of the legs are short. There are 15 legs in the 600-1200nm range which can be done with a Turtle tank (flexible bladder). This easily keeps within CG limits using a basic weight of 735 kg (1620lbs) and an aft empty CG of 109. These are the best empty figures I can find ... if anyone can update these figures that too would be helpful. The really serious leg is the Hilo to Oakland leg which is 2039nm. For that leg, it requires two Turtle tanks; one in the front seat and the other in the rear with only survival gear on board. It requires the winds to be at least an average of zero headwind (if I take off at MTOW). I will be carrying 3 E size oxygen bottles to do 5 hours at 18,000 to get out of the trade winds at lower levels and pick up tailwinds. With this configuration I can't quite keep my 90 minutes reserve fuel (IFR alternate +45 minutes is less but I want more contingency). In April the upper winds above 10,000' average between 0 and 25 knots TW . 15 knots tailwind saves 45 litres of fuel (another hours endurance)...so picking the right day is essential.

Apparently many ferry pilots take off up to 10-15% over MTOW. Another 30 kg (66lbs) overweight would give me my full 90 minutes if zero TW. I would prefer to keep it under MTOW and wait for a better day. If this leg is too hard, we can route via Phillipines Taiwan Japan Aleutian Islands Anchorage....but we have to do this in summer. I would've already crossed the North Atlantic in summer so it extends the whole trip from 8 months to 13 months by having to wait for the next summer to cross the northern Pacific.

I'd love to get feedback on your basic weight/ moment arm too!!
 
RV10Kiwi said:
Most of the legs are short. There are 15 legs in the 600-1200nm range which can be done with a Turtle tank (flexible bladder). This easily keeps within CG limits using a basic weight of 735 kg (1620lbs) and an aft empty CG of 109. These are the best empty figures I can find ... if anyone can update these figures that too would be helpful. The really serious leg is the Hilo to Oakland leg which is 2039nm. For that leg, it requires two Turtle tanks; one in the front seat and the other in the rear with only survival gear on board. It requires the winds to be at least an average of zero headwind (if I take off at MTOW). I will be carrying 3 E size oxygen bottles to do 5 hours at 18,000 to get out of the trade winds at lower levels and pick up tailwinds. With this configuration I can't quite keep my 90 minutes reserve fuel (IFR alternate +45 minutes is less but I want more contingency). In April the upper winds above 10,000' average between 0 and 25 knots TW . 15 knots tailwind saves 45 litres of fuel (another hours endurance)...so picking the right day is essential.

Apparently many ferry pilots take off up to 10-15% over MTOW. Another 30 kg (66lbs) overweight would give me my full 90 minutes if zero TW. I would prefer to keep it under MTOW and wait for a better day. If this leg is too hard, we can route via Phillipines Taiwan Japan Aleutian Islands Anchorage....but we have to do this in summer. I would've already crossed the North Atlantic in summer so it extends the whole trip from 8 months to 13 months by having to wait for the next summer to cross the northern Pacific.

I'd love to get feedback on your basic weight/ moment arm too!!
Click to expand...
When I did the test flying on my -10, I flew it at 2800 pounds (and wrote the paperwork that way too). I don't use the extra 100 pounds, but could if necessary - the airplane flies fine. You probably want to start with an airplane that has the large aftermarket leading edge tanks which hold 90 gallons. Looking at fuel requirements, 2300 NM/160 knots = 14.4 hours. 14.4 hours x 11 GPH = 160 gallons. 160 gallons x 6 lbs = 960 lbs of fuel. Add a 1700 lb airplane (probably achievable by stripping the interior and adding tankage in the cabin). If you weigh 200 lbs and your survival gear weighs 100 lbs, you'll be in the neighborhood of 3,000 lbs. That's kind of a worst case scenario. By flying slower and higher, you should be able to realize better economy, but I don't have any data on that. FYI, my typical cruise is 165 knots/10.5 GPH at 10,500. You mention 02 - you might consider an oxygen concentrator instead of 02 bottles and save a few pounds.
 
Kyle Boatright said:
When I did the test flying on my -10, I flew it at 2800 pounds (and wrote the paperwork that way too). I don't use the extra 100 pounds, but could if necessary - the airplane flies fine. You probably want to start with an airplane that has the large aftermarket leading edge tanks which hold 90 gallons. Looking at fuel requirements, 2300 NM/160 knots = 14.4 hours. 14.4 hours x 11 GPH = 160 gallons. 160 gallons x 6 lbs = 960 lbs of fuel. Add a 1700 lb airplane (probably achievable by stripping the interior and adding tankage in the cabin). If you weigh 200 lbs and your survival gear weighs 100 lbs, you'll be in the neighborhood of 3,000 lbs. That's kind of a worst case scenario. By flying slower and higher, you should be able to realize better economy, but I don't have any data on that. FYI, my typical cruise is 165 knots/10.5 GPH at 10,500. You mention 02 - you might consider an oxygen concentrator instead of 02 bottles and save a few pounds.
Click to expand...
Thanks for your info. I will look at the Oxy Concentrators. They seem pretty light weight and perform pretty well. With that longest leg of 2039nm I'm trying to eliminate as many single point failures as I can eg I NEED to go to 18000 to pick up the tailwinds and the concentrator fails I'm stuck. But they're such light weight you could carry two as a backup. Thanks for your help....
 
Kyle Boatright said:
When I did the test flying on my -10, I flew it at 2800 pounds (and wrote the paperwork that way too). I don't use the extra 100 pounds, but could if necessary - the airplane flies fine. You probably want to start with an airplane that has the large aftermarket leading edge tanks which hold 90 gallons. Looking at fuel requirements, 2300 NM/160 knots = 14.4 hours. 14.4 hours x 11 GPH = 160 gallons. 160 gallons x 6 lbs = 960 lbs of fuel. Add a 1700 lb airplane (probably achievable by stripping the interior and adding tankage in the cabin). If you weigh 200 lbs and your survival gear weighs 100 lbs, you'll be in the neighborhood of 3,000 lbs. That's kind of a worst case scenario. By flying slower and higher, you should be able to realize better economy, but I don't have any data on that. FYI, my typical cruise is 165 knots/10.5 GPH at 10,500. You mention 02 - you might consider an oxygen concentrator instead of 02 bottles and save a few pounds.
Click to expand...
At 15,000’ i get 165 knots tas at 9.5 gph or less. Even near gross. That is with adjustable ignition advance running lop. Suspect 2-4 knots less at 25*. I also get [email protected] at 10k, so similar performance.
 
lr172 said:
At 15,000’ i get 165 knots tas at 9.5 gph or less. Even near gross. That is with adjustable ignition advance running lop. Suspect 2-4 knots less at 25*. I also get [email protected] at 10k, so similar performance.
Click to expand...
Wow. Thats impressive!! Thanks. I’d love to get a few others experiences if similar performances to build a database. Thanks.
 
RV10Kiwi said:
Wow. Thats impressive!! Thanks. I’d love to get a few others experiences if similar performances to build a database. Thanks.
Click to expand...
I get similar. I do notice a few kts quicker if light.
The way I tend to think about it is that LOP I can plan on 165KTAS. At 8k that might be say 11.5 GPH but that decreases to 9.5-10 at 15k. But the 165 stays more or less the same and I speed up by a few kts over a long flight as I get lighter.
If I bump the FF up by 2GPH I go 6-8kts quicker. But I rarely do that.
 
Richard Connell said:
I get similar. I do notice a few kts quicker if light.
The way I tend to think about it is that LOP I can plan on 165KTAS. At 8k that might be say 11.5 GPH but that decreases to 9.5-10 at 15k. But the 165 stays more or less the same and I speed up by a few kts over a long flight as I get lighter.
If I bump the FF up by 2GPH I go 6-8kts quicker. But I rarely do that.
Click to expand...
Thank you for your info. That's a big change between 8000 and 15,000'. Do you use an oxygen concentrator for 15,000' (or bottles)?. If so, what type?
 
RV10Kiwi said:
Thank you for your info. That's a big change between 8000 and 15,000'. Do you use an oxygen concentrator for 15,000' (or bottles)?. If so, what type?
Click to expand...
I have a MH system with CFFC -048 tank.
Good for about 1300L. Which is 80h for one person.
In reality I fill it about once a year.
IMG_6267.jpeg
 
RV10Kiwi said:
Thank you for your info. That's a big change between 8000 and 15,000'. Do you use an oxygen concentrator for 15,000' (or bottles)?. If so, what type?
Click to expand...
This is the benefit of the 10's over powered design. The combined drag profile decreases with the less dense air. Engine power output is also dropping off, but the extensive reserve power available, allows you to still make good speed in this more efficient environment. Getting up high can really extend range. I have been able to make it non stop from chicago to dallas a few times with vfr reserves.
 
There are some RV-10 performance numbers in this thread (link below), including GPH, at various speeds and altitudes and mixture settings.

Not much about how that changes as a factor of weight, but as Breguet tells us, you can assume that at a certain L/D, a decrease in weight can be associated with a proportional decrease in drag...

RV-10 Performance numbers

I am disappointed when I saw the performance numbers posted thus far by the flying RV10s...they are SLOWWW Tim Olson had 161 kts with 22 mp and 2350 RPM ......151kts at 21.5 MP and 2350 RPM........I remember Glen Thomson and others have been posting similar numbers....I have not seen any with...
vansairforce.net
 
Oh, and: How soon do you want to do this? I ask because there is a DeltaHawk installation currently being developed for the RV-10, which would be a big help in your MPG. (Of course, there already is a diesel engine installation for the RV-10 offering higher MPG, but it has issues...).

And, as others have mentioned, Extended-Range tanks are available for the RV-10. Van's seems to be very concerned about the possibility of flutter with these tanks (I deduce from the substantial speed restrictions recommended by the company, and from how at one point Van's basically made you promise to not install these tanks when you ordered extra parts), but the engineer who developed them (and who used to be an engineer at Van's) has published an analysis explaining why he has no flutter concerns. So, there's a little bit of a "Who do you trust?" factor here. (Luckily for you, you probably get better MPG flying a little more slowly anyways, so, hopefully this is a non-issue for you).
 
Last edited:
AeroEngineer said:
Oh, and: How soon do you want to do this? I ask because there is a DeltaHawk installation currently being developed for the RV-10, which would be a big help in your MPG. (Of course, there already is a diesel engine installation for the RV-10 offering higher MPG, but it has issues...).

And, as others have mentioned, Extended-Range tanks are available for the RV-10. Van's seems to be very concerned about the possibility of flutter with these tanks (I deduce from the substantial speed restrictions recommended by the company, and from how at one point Van's basically made you promise to not install these tanks when you ordered extra parts), but the engineer who developed them (and who used to be an engineer at Van's) has published an analysis explaining why he has no flutter concerns. So, there's a little bit of a "Who do you trust?" factor here. (Luckily for you, you probably get better MPG flying a little more slowly anyways, so, hopefully this is a non-issue for you).
Click to expand...
Thanks for that. There's a lot of performance numbers on that 'performance' thread. The Delta Hawk is interesting but I won't have time for many mods as I will fly to the US buy, minor mods (Turtle tanks etc) test fly for a month, return to NZ, then return again to set off. I'd love to get the extended tanks but it's really hard to find a newish aircraft with those tanks. I'm not too concerned about Vans comments/restrictions...they have to speak to the whole flight envelope....I will be nowhere near any speed limits/G loadings. Cheers
 
RV10Kiwi said:
Thank you for your info. That's a big change between 8000 and 15,000'. Do you use an oxygen concentrator for 15,000' (or bottles)?. If so, what type?
Click to expand...
I have used a O2 concentrator (inogen) for two people at 17, 500 (running 5lpm). def lighter than a few o2 tanks. Ours was good until we blew a fuse and lost the 12v, not sure if it was the inogen (borrowed), or the aircraft fuse.
 
An entire MH EDS 4place system installed weighs 8lb empty and 10lb full.
An innogen G5 weighs 5lb. If you want (need) a backup that’s 10lb.
A wash if you ask me.
 
RV10Kiwi said:
Wow. Thats impressive!! Thanks. I’d love to get a few others experiences if similar performances to build a database. Thanks.
Click to expand...
My own numbers are quite similar to those posted by Larry and Kyle at the beginning of this thread. I see a reference further down to some slower and thirstier RV-10s, all I can say is that isn't my personal reality. I analyze data for entertainment (nerdy, I know), here is a link to a post with some coefficients for the effects of weight and altitude: https://vansairforce.net/threads/on-weight-and-tas.242178/post-1919576
 
You must log in or register to reply here.
Back
Top