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Fuel prices get me down...
Posted: Tue Jul 17, 2007 4:53 pm
by cjensen
Does anyone else get REALLY bummed about fuel prices, and the thought of flying your newly finished airplane on this stuff at the end? Silly question, I know...
I was on a real downer last night while out in the garage looking at all the parts I've created to this point, and thinking about the expense of flying it at the end.
Fuel prices at the "local" regional airports in my area are OVER $5/gal, and the cheaper small fields are creeping over $4/gal.
I guess I wonder where the "cutoff" will be when people will just say "That's it! I'm done."
By no means am I saying I won't finish (I WILL) or won't fly (I WILL FIND A WAY), it just bugs me to think about sometimes.

Posted: Tue Jul 17, 2007 5:19 pm
by Spike
The cost of building the plane is more depressing than fuel. I figure fuel is just a small percentage of the total cost. Im more worried about the $22K engine, etc.
Posted: Tue Jul 17, 2007 5:32 pm
by rv8or
I think about it constantly! In the military, then with the airlines, with no real GA experience, I never realized how much the fuel cost. Then I started the Lear Jet thing, and got to see it posted in every FBO I walked into...YIKES!

Glad I'm back in the terminals, instead of the FBOs, now.
I always had the fuel economy of my RV in mind...one of the reasons I vacilated between a -10 and the -8 I finally decided to build.
What can you do? Keep it lite, pick a good engine/setup, and hope for the best. Abandoning the project/goal is not an option any of us want to consider. Like you say, we'll find a way.
I look at the kit as a one time cost, but the fuel as a never ending need; so yes, I do get bummed thinking about it sometimes.
Joe
PS...There's always bannana peels

Posted: Tue Jul 17, 2007 5:59 pm
by RV7Factory
Like our friend Joe, I think about it a lot. Then I think to myself, what's more expensive, the cost of fuel, or the cost of regret for not following through with this?
Chad, it could be worse... you could play golf for a hobby. Have you seen how expensive a round of golf can be? Aye carumba!
Re: Fuel prices get me down...
Posted: Tue Jul 17, 2007 6:08 pm
by RV7Factory
cjensen wrote:I guess I wonder where the "cutoff" will be when people will just say "That's it! I'm done."
I don't think many will throw in the towel. I think the majority of Americans talk a good game, but have no interest in actually changing their habits. For example, sales of SUVs are at record highs, and the automakers just keep one-uping each other with bigger more powerful engines. Why? Because it's what the consumers want. Just last week I was reading one of the auto-mags and he feature article was about a bunch of 400+HP sports/muscle cars that will hit the market in the next year. Nobody NEEDS 450HP, but they sure want it. Just my $.02.
Posted: Tue Jul 17, 2007 6:26 pm
by painless
I find myself looking the other way when I swipe my card at the self-serve pump at MNM lately. I figure I didn't spend 9.5 years to build a lawn ornament, so I just remember the same quote that motivated me to build this airplane in the first place:
"Sometimes in life you just have to say, 'screw it...I'm doing this!'"

Posted: Tue Jul 17, 2007 6:44 pm
by cjensen
painless wrote:"Sometimes in life you just have to say, 'screw it...I'm doing this!'"

Ha! I can't say how many times I've said that line! Good call Jeff!
Brad, I completely agree with you on the general consensus that most Americans are a lot of talk with little or no plans to change anything. I'm one of 'em...although I do TRY and avoid unecessary travels (and rounds of golf)...we are guilty of buying one of the bigger SUV's in the last couple of years.

And if I could afford one, I'd be in line for a 400hp sports car as well!
Oh, and the other good one to keep in mind is..."You can't take it with you!"
Just sucks to think about it...
Posted: Tue Jul 17, 2007 7:37 pm
by Womack2005
I can't wait to throw the clubs in the RV and fly to a yet unplayed course who knows where!!!
I already have the loan application filled out for the tank of gas and the greens fees

3rd mortgage here I come!
If I build it they will come (read: I will pay)!
Posted: Tue Jul 17, 2007 9:59 pm
by TomC
Hi Chad,
The cost of fuel really does get one down! I find myself letting my plane sit because of high gas costs. On a related note, I got 2 oil filters from ACS a few weeks back. With shipping, the total came to almost $48. Since I change the oil every 25 hours, this works out to about $1 per hour for a simple oil filter. Oh well! With the high price of gas, I called Mahlon at Mattituck recently about running auto fuel in my engine (I got it from Mattituck). At first he said fine but then changed his mind when he looked up that I have one electronic ignition. He said that it advances the spark enough that I could experience detonation which could blow a hole in a piston. That ruined my thought of running auto fuel at around $3.20 a gallon. About my only option will be to find a partner who has similar flying habits and share the fixed costs. As others have said, however, I will not give up and quit.

Posted: Tue Jul 17, 2007 10:44 pm
by tshort
I just got back from filling the skyhawk (good excuse to fly) ... 4.10 / gal, cost me 150+ to fill up.
I don't worry about me as such - I will give up and quit other things before I stop flying, but I am worried about GA as a whole. I was actually thinking about that as I taxied back to the hangar tonight. Do you think there will be a time in our lifetime where we won't be able to fire up an internal combustion engine and go flying on a summer evening? What would happen to all these great old airplanes - the Stearman's, Waco's, and other classics? I just hope that our particular special interest group has enough clout to keep flying
T.
Posted: Tue Jul 17, 2007 11:22 pm
by 1:1_Scale
I've been thinking about this from the start (have I really started yet? lol). My initial goal was 30-35mpg at 200mph cruise. I figure if I can get the same milage as my car, but cut the travel time by 2/3rds I'll be happy. That's why I'm really looking at (and hoping for) the Deltahawk. Some of my flying relatives live about 240 miles away by air, and they were mentioning how if I had my PPL (I had to quit working on it due to the move) and a 172, I could fly up and visit more frequently. Then I started to do the math for fuel costs- it would take about 1/2 the time to fly up as it would to drive, but cost twice as much in fuel

Maybe thats the price you pay, but I think we can do better
Then I got to go to a presentation by Dave Anders that really got my hopes up. If you're not familiar with him, long story short is he has an RV-4 that tops out north of 265mph

He didn't get there by simply making the engine more powerful though. He started with a 220mph top speed and has calculated that 19.5 mph was gained from the engine/prop combo, and 24.5mph was due to drag reduction. He reduced the total airframe drag
27%. So what does this mean for fuel economy? At 14,000' and 190mph ground speed, Dave is burning 4.5gph for about 42mpg with an IO-360
So now I have even more hope! Dave estimates his engine's Brake Specific Fuel Consumption to be about .44. The DH is supposed to be .37-.39. Dave also estimates his propeller efficiency to be 80.5%. Paul Lipps claims his design program predicted that his propeller design is about 90% efficient. Hopefully his propeller will be avaliable for purchase in the near future

So I guess we should concentrate on reducing airframe and cooling drag as much as possible, and research propellers based on efficency, not to mention engines

Posted: Wed Jul 18, 2007 6:16 am
by captain_john
painless wrote:I find myself looking the other way when I swipe my card at the self-serve pump at MNM lately. I figure I didn't spend 9.5 years to build a lawn ornament, so I just remember the same quote that motivated me to build this airplane in the first place:
"Sometimes in life you just have to say, 'screw it...I'm doing this!'"

Jeff, you said a mouthful! I agree entirely!
The way I see it, the cost of renting the plane would be much higher!
If you look at it that way, the cost of flying is coming DOWN!
I sound like an addict justifying his addiction!
Let's say you fly an Arrow for 3 hours. Wet, it would cost about $375!
Fuel for the RV would only be about 30 Gallons or so. Probably less...
At $5 per gallon, that would be about $150, but I get a WAY BETTER PLANE!
I am not happy about fuel prices by no means. I am more threatened by USER FEES!!!

CJ
Try it on this side Atlantic
Posted: Wed Jul 18, 2007 6:49 am
by pgroell
Hello all,
to cheer you up a bit, why not think about our prices in Europe , at my airport LFPL east of Paris.
1.63€ per liter, so that's at the today's rate : 8.36$ per gallon.
Maybe it would make some sense to add long range tanks to my RV to get some 100LL in the US.
Well, I'm still building on.
Posted: Wed Jul 18, 2007 1:55 pm
by cjensen
captain_john wrote:The way I see it, the cost of renting the plane would be much higher!
If you look at it that way, the cost of flying is coming DOWN!
Yeah, that's why I don't rent much, if at all. I beg, borrow, and steal.
captain_john wrote:I sound like an addict justifying his addiction!
Yes, you do.
captain_john wrote:I am not happy about fuel prices by no means. I am more threatened by USER FEES!!!
Well, this is a debate for another thread, but I can see why it is threatening to corporate GA using the system flying IFR all the time, but flying around in an RV, VFR, without ATC service should still be manageable.
Back to fuel...I've been doing some reading since I posted this last night on various forums, and it seems that several are using 320's in 7's with great success, and good performance vs. fuel burn. I considered this at one point last year (what HAVEN'T I considered...), and I don't know why I dropped it.
One may sacrifice 7mph in cruise speed, but burn 2gph less? Almost seems fair...and the 320's are cheaper to work on and overhaul...hmmm...

Posted: Wed Jul 18, 2007 2:28 pm
by RV7Factory
Chad what about the IOX-340? What are the burns on that like?
Posted: Wed Jul 18, 2007 2:34 pm
by cjensen
It's on my list, and I've talked to Robbie Attaway about it several times. I even have the mini poster on my wall in the garage..."Stroker"
It burns 10.6gph at 75% and 9.2 at 65%. I think it's more a function of hp, not displacement for fuel burns.
Here's the ECi Comparison page...
http://www.eci2fly.com/exp/eng_comparisons11x17.pdf
Posted: Wed Jul 18, 2007 3:01 pm
by smithhb
While my -9 has a different mission profile than a -7 or -8, as well as a different design limitation by Vans, I was strongly considering an ECI IO-360 with 7.5:1 compression pistons. This would only be about 20# more than the -320 but with a Catto prop (16#s).
The biggest advantage is I could burn 92 octane OR 100LL, and still pump out about 166HP.
Thoughts?
Posted: Wed Jul 18, 2007 3:19 pm
by RV7Factory
Bret, If I look at the comparison chart Chad linked us to, the IO-360 at 7.2:1 is putting out 178HP (would be a touch higher with 7.5:1). Where is your 166 number coming from? I am genuinely curious... Thanks.
Posted: Wed Jul 18, 2007 3:29 pm
by rv8or
Chad--
I've been chewing on that -340 Stroker too. I'm seriously thinking about the -320s now as fuel continues to climb and my decision point gets closer.
Luckily, I've got you intrepid path finders ahead of me! CJ, how about a group buy on ENGINES!!!
Joe
Posted: Wed Jul 18, 2007 3:38 pm
by cjensen
There's a guy up in the Chicago area that has an O-320 in his RV-8, and he LOVES it! He's a an airline pilot by trade, but he can't speak highly enough about the combination of economy and speed the 320 offers him and his 8. He comes down here frequently during the school year to drop off and pick up his daughter from college, and I usually get a chance to chat with him...never says anything but good things about the engine.
