Today's Message Index:
----------------------
1. 03:39 AM - Re: Flight Test Progress (JOHNTMEY@aol.com)
2. 09:00 AM - new Rocket data (Frazier, Vincent A)
3. 09:27 AM - vapor lock (Frazier, Vincent A)
4. 09:28 PM - Re: new Rocket data (f1rocket@telus.net)
Message 1
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| Subject: | Re: Flight Test Progress |
--> Rocket-List message posted by: JOHNTMEY@aol.com
For e-hale, wondering what your symptoms are (vapor lock). So far, I have
recovered mine from the hottest of starts and when I notice flicker of fuel
pressure in flight, I give minute of boost pump and it soon stablilizes.
Anyone. When I shoot the fuel pump, the fuel flow instrument shows some
increase in fuel flow (cruise flight). Where does that fuel go ? I don't think
it goes thru the cylinders... there is absolutely no change to the analyzer
instrument. Eh ?
Continentals have a fuel return but not Lycomings. I did buy the Airflow
mechanically-selected fuel-bypass-return valve... and I have used it for hot
starts, but I'm not sure it really does anything.
jtm N5800
Message 2
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Cc: <rocket-list@matronics.com>
--> Rocket-List message posted by: "Frazier, Vincent A" <VFrazier@usi.edu>
John and Nico,
Hi guys. I've attached a spreadsheet of data that I've collected.
Notice that I didn't say it was GOOD data, but most of it is reliable
enough to make some comparisons.
John, congrats on the first 15 hours. I know you're having fun now.
If you look at the spreadsheet you will notice that the initial data is
wacky due to sensor calibration issues with the fuel flow, OAT, etc. My
OAT gauge is simply in a bad spot and reads at least 15 to 20 too high.
FWIW, the OAT is in the cabin air inlets on the side of the forward
fuselage.... a HOT place to sample the air and I need to completely redo
the cabin air inlets before next summer. They suck hot air. Ugh.
Much too hot for comfort in the summertime.
Some of the data was collected with electronic ignition, which I removed
later. Two mags were used for almost all of the data.
Anyway, you might find a few pearls in there, if you can understand the
changes that I made during the last 95 flight hours. I'm sorry that I
didn't document it better as I went along.
In a nutshell, here are the changes that I've made and how they turned
out. Please refer to my website for additional info... it's all in
there somewhere. If you can't find it, send me an email and I'll see if
my pea-sized brain can recall it. ;-)
Worthwhile changes:
1) put a 1/8" spacer in between the #2 and #5 baffles and cylinder face.
That helped to cool both cylinders nicely. If you look at the
spreadsheet you'll see that #2 and #5 ran hot up until last summer when
I added the spacer.
2) cleaned out the casting flash that was left in the cylinder fins near
the exhaust valves.
3) seal all baffle leaks with RTV. It might not look as nice, but if
you get rid of the air leaks it really helps.
4) balance your injectors per Don Rivera's instructions
http://www.airflowperformance.com/. I still need to tweak mine a bit
more, but I run LOP almost all of the time (55% power or less has been
no problem whatsoever) and saving several gallons/hour is great. I can
fly with my RV buddies and burn the same or less fuel than them at the
same speeds. AND the temps all go DOWN.
http://vincesrocket.com/Engine%20and%20Prop.htm here's a link. I feel
that these first 4 things are HUGE in keeping the cylinders cool and
temps even. My CHTs are usually within 15 degrees of each other.
FWIW, Mark Frederick told me that my inlets were probably ramped all
wrong and my outlet was too small but that the temps and performance
that I'm getting made his opinion moot. Maybe my inlets and outlet
aren't optimal, but the proof is that my oil temps and my CHTs are LOW
even on 95 F humid Midwest summer days. I did add the lower cowl
louvers late last summer. They do reduce temps even more. I'm not sure
that I really need them, but I have the option of removing a sliding
cover to expose the louvers if I ever do want more cooling... maybe
someday I'll need them open for a full power race through Death Valley?
5) I put an airflow smoothing aluminum cover the lower engine mount.
You can see it at the bottom of this photo.
http://vincesrocket.com/2004-09-08/engine%20view%2014.jpg
6) I'm using a Positech cooler mounted in the center of the engine
behind the engine mount. It's a different installation than any I've
ever seen but it works very well. You'd never get it to fit if you have
a vacuum pump or mechanical tach drive in the way though.
I have a butterfly valve to control airflow to the cooler and it works
very well also. At any OAT ( other than yesterday when it was 10F OAT)
I can warm or cool the oil just by moving the valve. Yesterday after 30
minutes of flying the oil was at 180 F... not bad since it was so
freaking cold outside.
Things that didn't work:
Rose electronic ignition with the magneto pickup. No. Bad. One of
these days I'd like to try the electronic ignition with the front pickup
instead. Probably a LSE unit, but a Rose unit with the front pickup
would probably be fine.
<<N540VF data.xls>>
Your unusable fuel should be measured in ounces unless you are using a
flop tube.
My fuel pressure is 28psi with the boost pump on. It is rock solid
23psi when the boost pump is off.
I hope you find some useful info in all of this. YMMV!!!
Anyone on the Rocket list that wants the spreadsheet should email me
DIRECTLY and I'll send it to you. I'm sure that the Matronics email
program will strip it off of the list emails.
vfrazier@usi.edu
Vince
F-1H Rocket, N540VF
http://vincesrocket.com/
Message 3
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--> Rocket-List message posted by: "Frazier, Vincent A" <VFrazier@usi.edu>
From: Ernest Hale <ehale@cheyenne-enviro.com>
Subject: Re: Rocket-List: Flight Test Progress
--> Rocket-List message posted by: Ernest Hale
--> <ehale@cheyenne-enviro.com>
I have a terrible time with fuel pressure due to vapor lock as well, any
advice will be greatly appreciated, I have done just about everything I
can think of.
Ernest and others,
No 90 degree bends in the fuel lines, right? I'm sure you've already
done that.
An easy way to see if a heat shield would help keep the lines cooler is
to wrap the fuel lines in the engine compartment with ordinary aluminum
foil wherever they are near a heat source. If the foil, which is 97%
reflective, helps keep the heat away then you can add a permanent heat
shield or just make certain that the foil is in good shape.
I've got one spot where the fuel line passes very close to the exhaust
just behind the fuel controller and it's easy to keep that line wrapped
in foil in addition to the heat shield on the exhaust.
I have had a few of my exhaust pipe mounted heat shields fail and go out
the air outlet. Ugh. Found 'em on the runway when I came back to the
airport. But the foil stayed in place as a backup! Those problems are
behind me now, but I still have the foil over the firesleeve in a couple
tight spots.
YMMV.
Vince
Message 4
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| Subject: | Re: new Rocket data |
--> Rocket-List message posted by: f1rocket@telus.net
Vince:
Have you had any trouble with your exhaust moving? I've put a brace between
mine but maybe at the expense of air flow in that area.
Regards,
Jeff
Quoting "Frazier, Vincent A" <VFrazier@usi.edu>:
> --> Rocket-List message posted by: "Frazier, Vincent A" <VFrazier@usi.edu>
>
> John and Nico,
>
> Hi guys. I've attached a spreadsheet of data that I've collected.
> Notice that I didn't say it was GOOD data, but most of it is reliable
> enough to make some comparisons.
>
> John, congrats on the first 15 hours. I know you're having fun now.
>
> If you look at the spreadsheet you will notice that the initial data is
> wacky due to sensor calibration issues with the fuel flow, OAT, etc. My
> OAT gauge is simply in a bad spot and reads at least 15 to 20 too high.
>
> FWIW, the OAT is in the cabin air inlets on the side of the forward
> fuselage.... a HOT place to sample the air and I need to completely redo
> the cabin air inlets before next summer. They suck hot air. Ugh.
> Much too hot for comfort in the summertime.
>
> Some of the data was collected with electronic ignition, which I removed
> later. Two mags were used for almost all of the data.
>
> Anyway, you might find a few pearls in there, if you can understand the
> changes that I made during the last 95 flight hours. I'm sorry that I
> didn't document it better as I went along.
>
> In a nutshell, here are the changes that I've made and how they turned
> out. Please refer to my website for additional info... it's all in
> there somewhere. If you can't find it, send me an email and I'll see if
> my pea-sized brain can recall it. ;-)
>
> Worthwhile changes:
>
> 1) put a 1/8" spacer in between the #2 and #5 baffles and cylinder face.
> That helped to cool both cylinders nicely. If you look at the
> spreadsheet you'll see that #2 and #5 ran hot up until last summer when
> I added the spacer.
>
> 2) cleaned out the casting flash that was left in the cylinder fins near
> the exhaust valves.
>
> 3) seal all baffle leaks with RTV. It might not look as nice, but if
> you get rid of the air leaks it really helps.
>
> 4) balance your injectors per Don Rivera's instructions
> http://www.airflowperformance.com/. I still need to tweak mine a bit
> more, but I run LOP almost all of the time (55% power or less has been
> no problem whatsoever) and saving several gallons/hour is great. I can
> fly with my RV buddies and burn the same or less fuel than them at the
> same speeds. AND the temps all go DOWN.
>
> http://vincesrocket.com/Engine%20and%20Prop.htm here's a link. I feel
> that these first 4 things are HUGE in keeping the cylinders cool and
> temps even. My CHTs are usually within 15 degrees of each other.
>
> FWIW, Mark Frederick told me that my inlets were probably ramped all
> wrong and my outlet was too small but that the temps and performance
> that I'm getting made his opinion moot. Maybe my inlets and outlet
> aren't optimal, but the proof is that my oil temps and my CHTs are LOW
> even on 95 F humid Midwest summer days. I did add the lower cowl
> louvers late last summer. They do reduce temps even more. I'm not sure
> that I really need them, but I have the option of removing a sliding
> cover to expose the louvers if I ever do want more cooling... maybe
> someday I'll need them open for a full power race through Death Valley?
>
> 5) I put an airflow smoothing aluminum cover the lower engine mount.
> You can see it at the bottom of this photo.
> http://vincesrocket.com/2004-09-08/engine%20view%2014.jpg
>
> 6) I'm using a Positech cooler mounted in the center of the engine
> behind the engine mount. It's a different installation than any I've
> ever seen but it works very well. You'd never get it to fit if you have
> a vacuum pump or mechanical tach drive in the way though.
>
> I have a butterfly valve to control airflow to the cooler and it works
> very well also. At any OAT ( other than yesterday when it was 10F OAT)
> I can warm or cool the oil just by moving the valve. Yesterday after 30
> minutes of flying the oil was at 180 F... not bad since it was so
> freaking cold outside.
>
> Things that didn't work:
> Rose electronic ignition with the magneto pickup. No. Bad. One of
> these days I'd like to try the electronic ignition with the front pickup
> instead. Probably a LSE unit, but a Rose unit with the front pickup
> would probably be fine.
>
>
>
> <<N540VF data.xls>>
>
> Your unusable fuel should be measured in ounces unless you are using a
> flop tube.
>
> My fuel pressure is 28psi with the boost pump on. It is rock solid
> 23psi when the boost pump is off.
>
> I hope you find some useful info in all of this. YMMV!!!
>
> Anyone on the Rocket list that wants the spreadsheet should email me
> DIRECTLY and I'll send it to you. I'm sure that the Matronics email
> program will strip it off of the list emails.
>
> vfrazier@usi.edu
>
> Vince
> F-1H Rocket, N540VF
> http://vincesrocket.com/
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
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