It depends on the fuel tanks. Most HR2 have the 42 Gal tanks vs the F1 have the 52 Gal. I installed a 10 Gal Smoke/Ferry tank which gives me a total fuel load of 62 Gal. My range is about 900 nm. I typically cruise 193-195 KTAS and burn 10.5 GPH LOP.
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!
Should I buy a used Harmon/F1 Rocket or a normal RV?
- Thread starter Duncannon
- Start date
You can totally fly the F1 Rocket at RV speeds burning the same fuel. The question would be why? I have flown my F1 with many RV8 while cruising on their wing burning under 8 GPH with my throttle at 1/4 the travel forward. After 30 minutes, I have enough and tell my RV friend that I will meet them at destination. I have the AEIO-540 with 10:1 and Plasma 3. Cruise at 193-195 KTS burning 10.5 GPH. Nothing wrong with those numbers. Don't get me wrong, nothing wrong with any RV but the F1 is just a different beast with a significant amount more performance. The climb difference between the RV or F1 is massive. Insurance wise, I pay about 1700$ USD with full coverage but also have about 1500 hrs on F1. You can't go wrong with the RV8 or F1.....just depends on what you are willing to sacrificeThe very first plane I drove some years ago whilst looking to by an RV was a Rocket. I was impressed by its performance but at the gas station the “RV smile” would gave disappeared pretty quick! Felt like a tank to druve also.
Then I test flew an 8, nice, better handling and better gas economy for what you got in return. I ended up buying an 8 and loved it but it too was a tank to drive. Enter the RV4 in my life, I went the long way around to finally get the best compromise of all of them, the 4 is nimble, light and quick for the power plant combo (160/FP) For me it was no contest, Mr Vans got the design just right, sex soeak, cost of operation and of course that fighter style feel you only get with a proper design, tandem, diesnt get any better than thatEach to their own but life is good, very good in a 4
Toobuilder
Well Known Member
Rockets have a range on their throttle quadrant that matches “RV speed and fuel burn”. It’s about at half travel. No RV has a “Rocket range” on their throttle quadrant.
The MT 3 blade prop goes to coarse pitch, once it comes off the governor….The Rocket just has significantly higher wing loading, which is why it gives such a lovely, strong, precise feel to it…and my low pitch stops were set per the manuals.
The difference in an engine failure is simply that you’ll be doing 85mph as you came into flare down to about 70. without thrust over the elevator…so you’re moving at a pretty good clip. The 4 can be quite a bit slower, as in 70 gliding down and 55 or so in the flare.
I’m not saying the Rocket doesn’t glide well….it’s just faster and higher sink….no biggie.
schooner49
Member
Hi Duncannon
If you are concerned about fuel cost, dont buy an airplane.
We have both, an RV 4 and a Rocket. Love them both, but the Rocket is easier to get in and out of for me.
Mom likes the 4 as it is easier for her to get in and out of the back seat. Its an RG. Both have bigger fuel tanks than standard.
Bryan
If you are concerned about fuel cost, dont buy an airplane.
We have both, an RV 4 and a Rocket. Love them both, but the Rocket is easier to get in and out of for me.
Mom likes the 4 as it is easier for her to get in and out of the back seat. Its an RG. Both have bigger fuel tanks than standard.
Bryan
You have a RV-4 RG?
You must be mistaken, I don’t know of ANY propeller that goes to COARSE pitch when power is reduced and you “come off the Governor”. The governor is trying to maintain set RPM, as you reduce power, the prop moves fine as it’s attempting to keep RPM.
Yep. Sorry. Saw sdrawkcab (was backwards)
andoman
Well Known Member
To revisit the Raider side of the discussion:
I think a Harmon with a high output 4 Cyl engine might have an advantage over the Raider. That advantage being the higher GW of the Harmon due to the stiffer sport wing. I recall Vince saying that the F-4 Raider wing is the standard span -4 wing and that -4 loading should be respected.
With a significantly heavier engine and a slightly heavier fuselage the useful load might be rather low.
I think a Harmon with a high output 4 Cyl engine might have an advantage over the Raider. That advantage being the higher GW of the Harmon due to the stiffer sport wing. I recall Vince saying that the F-4 Raider wing is the standard span -4 wing and that -4 loading should be respected.
With a significantly heavier engine and a slightly heavier fuselage the useful load might be rather low.
While this drifts a little, it still seems germaine to OP question…
This idea is intriguing, but what are the thoughts out there about flying a high output smaller engine vs the bigger six that would (typically) be run under less demanding conditions (ie, compression ratios, internal pressures, etc).
I enjoy these Rocket discussions.
andoman
Well Known Member
Most of my Rocket flying is in formation with other RV’s. The 540 just loafs along. I have yet to ask for an inch…
All things being equal I should enjoy at least 33% more longevity, yes?
When I launch on an XC and fly at 55% power, wear and tear should be equal. I just get there quicker.
Speaking of quicker, to those that are in the camp of “I don’t mind flying slower in my non-rocket RV cuz it’s cheaper and I get to log more flight time. It’s all about flying, right?,” I say this: In my fantasy dream world where I’m the king, I would be the only car on the highway and there would be no speed limit. My car would have a big engine and go fast!!!! My smile would be huge in the tight twisties and bigger (if that’s possible) wide open on the straights.
In reality I’ll never own the roads, but in my Rocket I own the skies…
All things being equal I should enjoy at least 33% more longevity, yes?
When I launch on an XC and fly at 55% power, wear and tear should be equal. I just get there quicker.
Speaking of quicker, to those that are in the camp of “I don’t mind flying slower in my non-rocket RV cuz it’s cheaper and I get to log more flight time. It’s all about flying, right?,” I say this: In my fantasy dream world where I’m the king, I would be the only car on the highway and there would be no speed limit. My car would have a big engine and go fast!!!! My smile would be huge in the tight twisties and bigger (if that’s possible) wide open on the straights.
In reality I’ll never own the roads, but in my Rocket I own the skies…
I’m more concerned about the IO-540 engine & prop overhaul costs than anything.
Norman CYYJ
Well Known Member
Norman CYYJ
Well Known Member
Not to worry, you can't take it with you.
pjc
Well Known Member
Keep going! You’ll truly be delighted when you arrive at the 3.The very first plane I drove some years ago whilst looking to by an RV was a Rocket. I was impressed by its performance but at the gas station the “RV smile” would have disappeared pretty quick! Felt like a tank to drive also.
Then I test flew an 8, nice, better handling and better gas economy for what you got in return. I ended up buying an 8 and loved it but it too was a tank to drive. Enter the RV4 in my life, I went the long way around to finally get the best compromise of all of them, the 4 is nimble, light and quick for the power plant combo (160/FP) For me it was no contest, Mr Vans got the design just right, sex appeal, cost of operation and of course that fighter style feeling you only get with a proper design, tandem, doesn't get any better than that
andoman
Well Known Member
When I jumped into the Rocket project the engine was 0 since major but it had been pickled for 20 years. I got the project at a fair deal that would allow me to field IRAN it myself if I had to and still be a little ahead. I pulled the all the jugs and everything I could see looked clean. I won’t feel completely in the clear until about 500 hrs. So far so good at 125.
If you find a plane with a good engine history the risk is low. If the plan is to keep the plane for a couple decades and fly 1500 hrs or more, the increased overhaul cost of the 540 is manageable.
How much more is a 6 cyl to overhaul? $10K? $20K? Set aside an extra grand a year for that rainy day.
The prop overhaul is a wash.
This is the only correct answer!The answer, of course, is to have BOTH a Rocket and a -3……….
I know, I did fly a mates 3 after I bought my 8, it was a blast to drive but in the end the 4 suited me with the ability to share that smile with another, besides at the time I owned a Corby Starlet, poor man’s ‘3’ but was a fast fun little machine, sold it due age, they say age shall not weary them……bs, at 70 I was struggling to fit in the little shipKeep going! You’ll truly be delighted when you arrive at the 3.
Sounds like good logic, certainly works for meThe answer, of course, is to have BOTH a Rocket and a -3……….
I had a Corby Starlet for a while, it was a hoot to fly. Fast and responsive but a bit squirrelly on the ground. Not in a dangerous way but you really had to pay attention during taxi as it was a bit short coupled and could get away from you. You’re right though- it was a bit snug.I know, I did fly a mates 3 after I bought my 8, it was a blast to drive but in the end the 4 suited me with the ability to share that smile with another, besides at the time I owned a Corby Starlet, poor man’s ‘3’ but was a fast fun little machine, sold it due age, they say age shall not weary them……bs, at 70 I was struggling to fit in the little ship
Attachments
Still looking for just the right oneSo @olyolson, have you closed on your new Rocket purchase? Or was that supposed to be kept a secret?
The funny thing is, when I purchased the F1 kit about two yers ago, I said it woudl replace the RV-8. That is still my plan, but as I build on, and continue to put hours on the -8, I am constantly amazed at just how much I enjoy that airplane - simple, easy to fly, easy to land, easy to start (carbed)… and easy to insure. The Rocket will have to prove itself to me (as I always assumed it would have to do) when it is finished. But remember, for shear joy of flight, I have an RV-3! the RV-8/Rocket are transportation machines for me, not all-around single airplanes….
Just musing….
Jjackh10
Well Known Member
Planes are like guns, we build them, we buy them, we do not sell them.
Toobuilder
Well Known Member
Couple of weeks ago talked to a guy with an -8 and a Rocket. I explained that when I was in that situation the -8 just sat. His response was just the opposite - his Rocket just sits and the -8 is the favorite. Will be interesting to see where you land. As a metric, I don’t think there are many of us who own both and can fly each back to back and compare.
andoman
Well Known Member
Here are some more FF/speed nos. that show the versatility.
Pix are:
-Formation X/C cruising speed
-Rocket economy cruise speed
-Rocket “lighten the wallet” speed
Excuse: I think my Rocket is slow due to a large air intake inefficiency. The next time the cowl is off I’ll yank the tiny air filter to learn more.
Pix are:
-Formation X/C cruising speed
-Rocket economy cruise speed
-Rocket “lighten the wallet” speed
Excuse: I think my Rocket is slow due to a large air intake inefficiency. The next time the cowl is off I’ll yank the tiny air filter to learn more.
Attachments
Looks good
Mine was fast, gap seals, low racing canopy, would cruise @ VNE 138 kts on 80 HP, mini RV3/4 it was just a lot cheaper
vfrazier
Well Known Member
The F1 kits are available, just not QB kits.
Contact me directly if interested! [email protected]
Vince
vfrazier
Well Known Member
The F4 Raider is not a Harmon, although Larry Vetterman's former HR2 has a 4 cylinder and therefore is similar... but it's not an F4.
The F4's all have F1 gear.
The F4 Raider and the F1 Rocket have identical fuselages, but differ UNDER the cowling. The F4 "could" use RV-4 wings, or tails, but it isn't required to do so.
Last edited:
Toobuilder
Well Known Member
Concerning insurance, as the manufacturer of the machine, one is free to name it anything you want. In that case, might not want to pick a name that is on the insurance company’s black list.
How’s this baby coming along?
Attachments
vfrazier
Well Known Member
Everything will be ready on Tuesday!
Nice! Interesting that those are the same numbers I see (MAP, RPM, FF, IAS) cruising WOT at 10K. The TAS is just about 25 kts higher.
I’m looking forward to seeing what it will do closer to sea level. (My field elevation is almost 7,000’).
My “solo run to breakfast” power settings in my HRII are 2200rpm / 19” / 8.5gph which equates to 174 knots true airspeed. This, incidentally, is exactly the fuel flow setting and resulting true airspeed that my RV3 delivers at 2400rpm and 24” of manifold pressure. I’m fortunate to own some exceptional performers within their class!
I get similar cruise speeds up high but my FF is a bit higher than yours. I will see if I can add a few picks. Hopefully you get a chance to fly it low on a cold day. The performance is fantastic. I am under class B airspace and level off at 3500 feet. I have to pull power to avoid exceeding 200 KIAS. You can see by the pics pushing it up to 210 is a big waste of fuel.
Attachments
I wish I could have those fuel flows!I cruise at a bit lower FF. My SDS CPI2 allows a very lean mixture up high with very little speed penalty. My LOP advance is set at 37 degrees.
I wish I could get the higher MAP that you show.
I can fly well over 800 miles in 4 hours with 30 mi. Reserve in my F1. The rocket can also fly RV speeds, (why), and burn the same or less.
