Today's Message Index:
----------------------
1. 06:29 AM - Re: LOP (Milt)
2. 07:55 AM - Cat out of the bag - LONG (Wernerworld)
3. 11:33 AM - Re: Rocket vs. RV-7 (Bobby Sather)
Message 1
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--> Rocket-List message posted by: "Milt" <rocket@swmrmc.org>
Went to 8,000 feet Sunday.
EGT peaked at 1450 with CHT at 400.
Pulled mixture back to EGT of 1330 at 23" and 2200 RPM this gave me a fuel burn
of 9.8GPH and CHT @370 TAS 197 KTS
Normally at ROP and 23" and 2200RPM 8000' EGT is 1330 CHT 390 and burn is 14 GPH
TAS 202KTS
I had similar experience in pulling back further, the temps dropped precipitously
as did power.
I suspect my injectors must be fairly well balanced as I noticed no roughness in
the engine during the pullback.
Didn't remain there long as I do not have the full engine monitor array installed
yet.
I have to send my unit back to Blue mountain to have a new board installed for
the additional sensors.
Should have the new MT 3 blade installed at about the same time.
Can't wait until it's all done so I can take it high and see what it will do.
Saving 4-5 GPH will be phenomenal in extending the utility of the aircraft.
Currently when flying IFR I try to have it on the ground at 2 1/2 hrs so as to
have enough reserve for a missed and then an alternate.
I figure at 9GPH plus the climb I should be able to add an additional 200NM before
my 1st approach.
Message 2
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| Subject: | Cat out of the bag - LONG |
--> Rocket-List message posted by: "Wernerworld" <russ@wernerworld.com>
Rocketeers:
I've deliberately waited until this story was near conclusion before sharing
it with the list. We're about there now, so here goes.
Two months ago I was at the 26 hour point in my flight testing. Time to
start putting the inverted oil system through it's paces.
Just playing around, I pulled into a vertical climb at about 200 mph and as
the speed dropped to about 100 I started a gentle push out at about 1/2
negative G. Unbeknownst to me (then), that is a tough situation for the
Christen system. Anyway, the oil pressure was fine through the push, but as
I went back to 1 positive G the oil pressure dropped off and that caused the
(non-counterweighted) prop to start to speed up. Since the speed was slow,
I just pulled the power to idle (and the prop to course, but that didn't do
anything). About a minute later I shut off the ignition just after
touchdown. (This is why you do stuff like this near the field).
Lots of research and we decided that the upper ball didn't seat properly in
the Christen check valve. This was an erroneous assumption, as it turned
out later. Christen says that is common in a new system. All it takes is a
small sliver or filing to keep the ball from seating properly and allowing
air to the oil pump.
Okay, disassemble the entire Christen system and clean and inspect. Didn't
see anything and the check valve seats appeared to be perfect. When you
take it all apart oil goes everywhere and you wouldn't know if a sliver of
something got away or not.
Try again. This time I went up and made the mistake of being faster when
testing it. I pulled the nose up a bit and rolled over to inverted. As I
was watching the oil pressure and all, I mistakenly let the nose drop a bit
so, rather than push it up, I rolled back upright. In doing that, the nose
dropped further and speed was building. At the same time the oil pressure
went to zero and the engine and prop ran away. This time, with the extra
speed, the engine and prop over redline by a bunch (3450). Shit. I shut
off the ignition, and within a minute I was on the tarmac. Not a good day.
Even with the engine shut off and the prop control aft, the airloads on the
prop brought the RPM over redline as I was slowing.
I called Hartzell the next morning and they said that if you spin one of
their props more than 20% over redline it becomes scrap. Lycoming says if
you spin one of their engines that amount it is a mandatory overhaul. Nice.
Further investigation through Christen and others indicates that if you use
the vacuum pump pad as an oil pickup, plumbed as the Extra's are, you must
remove the drive gear and associated spacer or you will have a problem.
That problem is low oil pressure in inverted flight and the inability for
the balls to reseat when returning to upright flight. My engine builder,
who built the engine and supplied the inverted system including the vacuum
pad hose adapter neglected to remove this gear. The plumbing diagram came
from him as well.
I have now received my engine from the engine builder, back from a fresh
overhaul. No significant damage was found in the engine. I have a beauty
of a new MT counterweighted prop installed and flew yesterday for the first
time. I also have a polished spinner and a Czech governor for sale. These
are for the 2 blade Hartzell or, I believe the non-counterweighted MT's.
The MT is much smoother, except when it is reaching into your wallet!
The rest of the story is who paid for all this mess. I didn't come out too
bad, but I will relay the rest of that story soon, after everyone has a
chance to do the right thing. It appears most are stepping up.
This story is just one more part of this aviation thing, where you do
everything exactly as instructed and still get screwed. You wire up you new
super gizmo and it doesn't work or something like that. Nearly all the
problems (few) I've had are like that. It isn't the builder mistakes that
cause most of them it is the supplied equipment. That's what I have found,
anyway.
As for deadsticking the plane with a flat pitch prop, no big deal. I was
near the field and didn't have to stretch the glide, but other than that it
is as easy as any other landing. All the chatter about how you will drop
like a rock is bunk. Don't get slow and it is fine. If you don't have an
airport nearby, just pick a nice spot that is close and manage your speed
and it is fine. Get too slow and you WILL sink, big time. If your engine
is running and your non-counterweighted prop is not governed you won't get
jack for power to it before hitting the RPM redline. Start looking for a
place to land.
Many are going to have questions about this. Post them here and we'll get
some good stuff into the archives.
Fly safe. Practice for a bad day. Don't make your insurance guy tell your
spouse what a great guy you were.
Russ
Message 3
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--> Rocket-List message posted by: "Bobby Sather" <sather@charter.net>
The Rocket is the only way to go. BUT, this really caught my eye. Check
out this report. Shows what dedication can do. Maybe this guy ought to
check out the Rocket. Make me wonder what he could do with it.
http://members.eaa.org/home/flight_reports/triaviathon.html
Good Day
Bobby
-----Original Message-----
From: owner-rocket-list-server@matronics.com
[mailto:owner-rocket-list-server@matronics.com] On Behalf Of mark manda
Subject: Re: Rocket-List: Rocket vs. RV-7
--> Rocket-List message posted by: mark manda <mark2nite@yahoo.com>
I know a couple of guys at bakersfield's big field--
they have been working on their rockets for ten years
now. stop by and visit them.
I went for my first HR ride with jack at Riverside
muni. what a plane! no comparison to an RV. But I got
in and thought, were's my lunch box go? no seat next
to me.
mark
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