Today's Message Index:
----------------------
1. 05:43 AM - Re: The FireFly flies! (And it flies EXXCELLENT!) (George Helton)
2. 06:09 AM - Re: The FireFly flies! (And it flies EXXCELLENT!) (william sullivan)
3. 06:40 AM - Re: The FireFly flies! (And it flies EXXCELLENT!) (John Hauck)
4. 07:27 AM - relaying information (Larry Cottrell)
5. 07:32 AM - Re: The FireFly flies! (And it flies EXXCELLENT!) (Larry Cottrell)
6. 10:48 AM - Re: The FireFly flies! (And it flies EXXCELLENT!) (Richard Pike)
7. 10:59 AM - Re: Re: The FireFly flies! (And it flies EXXCELLENT!) (william sullivan)
8. 11:08 AM - Re: Re: The FireFly flies! (And it flies EXXCELLENT!) (John Hauck)
9. 11:47 AM - Re: Re: The FireFly flies! (And it flies EXXCELLENT!) (Bill Berle)
10. 02:19 PM - Re: The FireFly flies! (And it flies EXXCELLENT!) (Richard Pike)
11. 02:24 PM - Re: Re: The FireFly flies! (And it flies EXXCELLENT!) (Wayne Schneider)
12. 07:07 PM - Re: The FireFly flies! (And it flies EXXCELLENT!) (Richard Pike)
13. 07:33 PM - Shake (B Young)
14. 08:59 PM - Re: Re: The FireFly flies! (And it flies EXXCELLENT!) (Charlie England)
15. 10:12 PM - Re: The FireFly flies! (And it flies EXXCELLENT!) (wakataka)
Message 1
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
Hey Richard, congrats on getting the little bird flying! I liked the 1st flight
takeoff video. George
Have a great day!
> On Jul 18, 2017, at 11:17 PM, Richard Pike <thegreybaron@charter.net> wrote:
>
>
> Took it to the field of a friend, 3,000' grass strip (!) I flew it twice this
morning, took off, climbed to 30', flew it down the runway and landed. Went back
this evening to fly it some more, David & I both flew it for a total of 11
times, a bit over 2 hours. Burned 2.5 gallons of gas.
> The 277 seems to be plenty of power, but IMO it vibrates a bit much. Maybe I
am spoiled by 2 cylinder engines...
> Performance is ideal for an ultralight, cruises at 54 mph at 4900 rpm, climbout
at 45 indicated at 7-800 fpm. Should have gone ahead and put the requisite
trim tab on the right aileron, and then it would have been trimmed right to start
with. Will do that tomorrow.
> Extremely pleased.
> https://youtu.be/Rq8NCDpBg1A
>
> --------
> Richard Pike
> Kolb MKIII N420P (420ldPoops)
> Kingsport, TN 3TN0
>
> Forgiving is tough. Being forgiven is wonderful.
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=471150#471150
>
>
>
>
>
>
>
>
>
Message 2
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
It seemed to get up in the air really quickly. Any wind? What was the finished
weight?
Bill Sullivan
Windsor Locks, Ct.
--------------------------------------------
On Tue, 7/18/17, Richard Pike <thegreybaron@charter.net> wrote:
Subject: Kolb-List: The FireFly flies! (And it flies EXXCELLENT!)
To: kolb-list@matronics.com
Date: Tuesday, July 18, 2017, 11:17 PM
Pike" <thegreybaron@charter.net>
Took it to the field of a friend,
3,000' grass strip (!) I flew it twice this morning, took
off, climbed to 30', flew it down the runway and landed.
Went back this evening to fly it some more, David & I
both flew it for a total of 11 times, a bit over 2 hours.
Burned 2.5 gallons of gas.
The 277 seems to be plenty of power,
but IMO it vibrates a bit much.
--------
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
Message 3
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| Subject: | The FireFly flies! (And it flies EXXCELLENT!) |
Congratulations on the new Fire Fly.
Glad it performed well.
john h
mkIII
Titus, Alabama
-----Original Message-----
From: owner-kolb-list-server@matronics.com
[mailto:owner-kolb-list-server@matronics.com] On Behalf Of Richard Pike
Sent: Tuesday, July 18, 2017 10:18 PM
Subject: Kolb-List: The FireFly flies! (And it flies EXXCELLENT!)
--> <thegreybaron@charter.net>
Took it to the field of a friend, 3,000' grass strip (!) I flew it twice
this morning, took off, climbed to 30', flew it down the runway and landed.
Went back this evening to fly it some more, David & I both flew it for a
total of 11 times, a bit over 2 hours. Burned 2.5 gallons of gas.
The 277 seems to be plenty of power, but IMO it vibrates a bit much. Maybe I
am spoiled by 2 cylinder engines...
Performance is ideal for an ultralight, cruises at 54 mph at 4900 rpm,
climbout at 45 indicated at 7-800 fpm. Should have gone ahead and put the
requisite trim tab on the right aileron, and then it would have been trimmed
right to start with. Will do that tomorrow.
Extremely pleased.
https://youtu.be/Rq8NCDpBg1A
--------
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
Forgiving is tough. Being forgiven is wonderful.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=471150#471150
Message 4
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| Subject: | relaying information |
I received an email from a Northern flyer concerning an accident with his
plane. He did not wish to be identified for some reason. This is what I got.
Would you mind passing this on to the Kolb group? I'd like to not put my
name in with it.
I recently wrecked a perfectly good Kolb MK III and would like to pass on
a couple of comments.
You can see some details of the incident at:
http://www.summit107.com/news/east-kootenay-news/plane-crash
-near-creston-results-in-two-people-receiving-minor-injuries/
The engine was a beautifully converted Geo 4 cylinder that ran as smooth as
silk. This installation might be a little heavier than a 912 and a friend
predicted that in an accident the engine would be in our laps. In fact, as
you can see from the picture, there was next to no structural failure in
the cage/engine mount area in spite of a landing that wiped off the gear,
flattened the belly and essentially wrote off the plane.
I was the pilot and sustained minor back damage: lots of aches and pains
and a minor concussion (some memory loss of the last critical moments) but
nothing broken. My friend on the other hand had severe back damage as in a
broken back needing pins to fuse several vertebrae.She will recover most
function but will not likely be up to her pre-accident capability. It is
possible that her damage was caused by impact with the battery which was
under her seat. If I ever own another plane like this I would look into
some kind of rigid seat pan for back protection
Because of the memory loss, I cannot say for sure what happened. There was
a power reduction after take-off . I did push the nose down to go under
power lines. I did not pull up enough. Don't know why.
-----------------------------------------------------------------------------------------------------------------------------------------------------------------
One of the things that we could take away from this incident is that the
sling seats can be hazardous to your health.
Larry
--
*The older I get, the less tolerant I am of those who are intolerant of
others.*
*If you forward this email, or any part of it, please remove my email
address before sending.*
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
How in the world did you find an operating 277? It seemed to do just fine
with it. I am considering repainting my plane back to blue again. I'm
having a hard time sneaking up on my neighbor next door.
Congratulations
Larry
On Tue, Jul 18, 2017 at 9:17 PM, Richard Pike <thegreybaron@charter.net>
wrote:
>
> Took it to the field of a friend, 3,000' grass strip (!) I flew it twice
> this morning, took off, climbed to 30', flew it down the runway and landed.
> Went back this evening to fly it some more, David & I both flew it for a
> total of 11 times, a bit over 2 hours. Burned 2.5 gallons of gas.
> The 277 seems to be plenty of power, but IMO it vibrates a bit much. Maybe
> I am spoiled by 2 cylinder engines...
> Performance is ideal for an ultralight, cruises at 54 mph at 4900 rpm,
> climbout at 45 indicated at 7-800 fpm. Should have gone ahead and put the
> requisite trim tab on the right aileron, and then it would have been
> trimmed right to start with. Will do that tomorrow.
> Extremely pleased.
> https://youtu.be/Rq8NCDpBg1A
>
> --------
> Richard Pike
> Kolb MKIII N420P (420ldPoops)
> Kingsport, TN 3TN0
>
> Forgiving is tough. Being forgiven is wonderful.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=471150#471150
>
>
--
*The older I get, the less tolerant I am of those who are intolerant of
others.*
*If you forward this email, or any part of it, please remove my email
address before sending.*
Message 6
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
We are still struggling with the weight, our cheesy bathroom scales say it is ~260,
it could be legal, but we don't know what it actually weighs. Even with these
bogus scales it at least falls within the W&B envelope. Got an A&P friend
with real scales, will get him to weigh it. Anyway, it is very close to legal
U/L weight and we are not done fiddling with that part yet; we are determined
that it is going to end up legal.
Flight yesterday was with no wind, it accelerates slower on the flat than the other
Kolbs due to the small engine, but once it gets off, it climbs really good
because of the light weight.
We found a local guy who had purchased a 277 and sent it to Lockwood and had it
totally rebuilt, it has a 2.58:1 A box on it, 64" 2 blade Ivoprop. It runs really
smooth at cruise power, but vibrates a lot at idle, don't yet know why.
Will be putting a trim tab on the right aileron this evening and hoping to fly
it to it's permanent home. Nice little 28 mile cross country.
--------
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
Forgiving is tough. Being forgiven is wonderful.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=471168#471168
Message 7
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
Very nice. All I can suggest is to re-read Jack Hart's web site for dietary
suggestions. Anybody hear from him lately?
Bil Sullivan
--------------------------------------------
On Wed, 7/19/17, Richard Pike <thegreybaron@charter.net> wrote:
Subject: Kolb-List: Re: The FireFly flies! (And it flies EXXCELLENT!)
To: kolb-list@matronics.com
Date: Wednesday, July 19, 2017, 1:48 PM
Pike" <thegreybaron@charter.net>
We are still struggling with the
weight, our cheesy bathroom scales say it is ~260, it could
be legal, but we don't know what it actually weighs. Even
with these bogus scales it at least falls within the W&B
envelope.
Message 8
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
Does it still have the same vibration problem at high idle? At what RPM
does it clean up?
Over the years I have seen most folks try to slow idle all models of the
Rotax, while the engine it trying to eat itself with adverse feedback and
gear box chatter.
If it was mine, I'd idle it fast enough to get out of the vibrations mode,
if that is possible, and still being able to comfortably control the
aircraft.
john h
mkIII
Titus, Alabama
-----Original Message-----
From: owner-kolb-list-server@matronics.com
[mailto:owner-kolb-list-server@matronics.com] On Behalf Of Richard Pike
Sent: Wednesday, July 19, 2017 12:49 PM
Subject: Kolb-List: Re: The FireFly flies! (And it flies EXXCELLENT!)
--> <thegreybaron@charter.net>
We are still struggling with the weight, our cheesy bathroom scales say it
is ~260, it could be legal, but we don't know what it actually weighs. Even
with these bogus scales it at least falls within the W&B envelope. Got an
A&P friend with real scales, will get him to weigh it. Anyway, it is very
close to legal U/L weight and we are not done fiddling with that part yet;
we are determined that it is going to end up legal.
Flight yesterday was with no wind, it accelerates slower on the flat than
the other Kolbs due to the small engine, but once it gets off, it climbs
really good because of the light weight.
We found a local guy who had purchased a 277 and sent it to Lockwood and had
it totally rebuilt, it has a 2.58:1 A box on it, 64" 2 blade Ivoprop. It
runs really smooth at cruise power, but vibrates a lot at idle, don't yet
know why.
Will be putting a trim tab on the right aileron this evening and hoping to
fly it to it's permanent home. Nice little 28 mile cross country.
--------
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
Forgiving is tough. Being forgiven is wonderful.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=471168#471168
Message 9
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
On Wed, 7/19/17, John Hauck <jhauck@elmore.rr.com> wrote:
"... while the engine it trying to eat itself with adverse feedback and gear box
chatter.
If it was mine, I'd idle it fast enough to get out of the vibrations mode, ..."
Agree 100%. I have very little experience with 2 stroke engines, but I do know
that harmonic vibrations and harsh load reversals are bad for any engine. There
is little or no upside to operating any engine in an RPM range that creates
bad vicrations. Any experienced pilot will tell you that an airplane will "talk
to you" and tell you when it's happy or unhappy.
Message 10
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
It cleans up at around 3500. I am wondering if the power pulses of a single and
the coupling design of the A & B gearboxes is not going to make for a happy relationship?
Years ago I had a 277 on my Hummer with the Maxair belt drive and
it was smooth as silk. Might have to look into trying to scrounge up an old belt
redrive.
--------
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
Forgiving is tough. Being forgiven is wonderful.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=471173#471173
Message 11
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
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Message 12
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
Prop weight is well within range for an A or B box, it is a new two blade 64" Ivo,
so that is minimal, but something is screwy with whatever we are doing. We
idled it up to 3,000 minimum and got rid of all the single cylinder/gearbox shake
at idle, but then trying to land it was a pain - float and float some more.
So idled it back down to 2,200 so you can slow down on approach and then throttle
it right back up to 3,000 once you get down and settled. So you only have
a few moments of excessive shake.
But that is not the problem; the problem is that even when it is running comparitively
smoothly @ 3,000 rpm or over, this thing simply vibrates way more than
any airplane or U/L I have ever flown, something is not right.
The little engine runs fine, flew it a short 30 mile cross country this evening
from the big grass strip where we did our test flights to the field where it
will be living for the next few months, and the only rpm that doesn't vibrate
excessively is right at 5,200, everything else you can feel the vibration all
through the airframe.
Something Dave pointed out is that when we first got this airplane it had a 447
on it; after we put the airframe back together and ran it up, that engine vibrated
excessively just like this one does. I am starting to wonder about our Lord
mounts.
But right now we are open to all suggestions. Tomorrow I'll post some pictures
of the engine/mounts, etc.
--------
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0
Forgiving is tough. Being forgiven is wonderful.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=471178#471178
Message 13
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Have you thought of trying a difference prop to check for shaking at
different rpms
Do not archive
Boyd
Message 14
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
On 7/19/2017 9:06 PM, Richard Pike wrote:
>
> Prop weight is well within range for an A or B box, it is a new two blade 64"
Ivo, so that is minimal, but something is screwy with whatever we are doing.
We idled it up to 3,000 minimum and got rid of all the single cylinder/gearbox
shake at idle, but then trying to land it was a pain - float and float some more.
So idled it back down to 2,200 so you can slow down on approach and then
throttle it right back up to 3,000 once you get down and settled. So you only
have a few moments of excessive shake.
>
> But that is not the problem; the problem is that even when it is running comparitively
smoothly @ 3,000 rpm or over, this thing simply vibrates way more than
any airplane or U/L I have ever flown, something is not right.
>
> The little engine runs fine, flew it a short 30 mile cross country this evening
from the big grass strip where we did our test flights to the field where it
will be living for the next few months, and the only rpm that doesn't vibrate
excessively is right at 5,200, everything else you can feel the vibration all
through the airframe.
>
> Something Dave pointed out is that when we first got this airplane it had a 447
on it; after we put the airframe back together and ran it up, that engine vibrated
excessively just like this one does. I am starting to wonder about our
Lord mounts.
>
> But right now we are open to all suggestions. Tomorrow I'll post some pictures
of the engine/mounts, etc.
>
> --------
> Richard Pike
> Kolb MKIII N420P (420ldPoops)
> Kingsport, TN 3TN0
>
Richard,
I don't remember seeing many UL/light plane guys talk about prop
balance; particularly dynamic balance. But it might be worth a look,
especially if an EAA chapter nearby has a dynamic prop balancer for loan
or rent (ours does, here in central MS).
What you're describing could easily be caused by prop imbalance. It's
the nature of the beast that we notice lower frequency vibes, but are
not sensitive to higher frequencies. So your vibe may be there all
across the rpm spectrum, but you just can't feel it when the engine's
running at higher rpm.
There's also the issue of resonance. Your particular combination of
prop, gearbox, engine, airframe, mount cushions, etc may be near its
system resonance in the range they you're able to idle the engine
effectively. Any imbalance may be conspiring with a possible resonant
freq that's near your idle rpm to give you severe vibes in that range.
Without actual data it's just wild speculation, but something to consider.
Charlie
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| Subject: | Re: The FireFly flies! (And it flies EXXCELLENT!) |
Richard -
Congratulations on the successful first flight. I had about 100 hours on 277 engines
before I went to Kawasaki, mainly to avoid vibration that was tearing up
my airframe. The 277 is a really powerful and light weight little engine, but
it does vibrate more than any 2 cylinder I've ever flown. I had one of those
dynamic prop balancer thingies on mine and it helped just a bit. Not sure it was
worth the extra weight, particularly if you are striving to make it legal.
One thing you might want to check the spring washers in the gearbox. If spring
washers get weak there will be excessive 'give' in the knuckle joint. It can make
the engine shake really bad at low RPM. If you're hearing a clacking noise
associated with the vibration, suspect your spring washers. There was a service
bulletin on the A gearbox. It originally had something like 9 spring washers
and it was updated to 12. Same shaft, just more washers packed onto it to tighten
up the knuckle joint. B boxes always had the larger number of spring washers.
I'll try to attach the service bulletin and the gearbox repair instructions
from the CPS catalog.
I was able to do the spring washer replacement in a big bench vise using a big
socket in place of the special Rotax tool, which is no longer available. If you
read the Rotax manuals, they say the spring washers should be replaced something
like every 100 hours. Nobody I know does that, but if the spring washers
do get weak, it will make your engine shake like crazy, be hard to start, and
sometimes hard to get to come off idle.
--------
There is something fascinating about science. One gets such wholesale returns of
conjecture out of such a trifling investment of fact.
Mark Twain
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=471181#471181
Attachments:
http://forums.matronics.com//files/gearboxupdateinstructions_389.pdf
http://forums.matronics.com//files/gearboxrepair2_704.pdf
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