Today's Message Index:
----------------------
1. 07:47 AM - elevator balance (BOB TRIPP)
2. 08:25 AM - Re: elevator balance (Peter Cattoni)
3. 09:35 AM - Re: elevator balance ()
Message 1
INDEX | Back to Main INDEX |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | elevator balance |
We are in the final stages of assembling our MYSTERIOUS MOOSE at a
hangar in Arlington Airport. Most of the problems we have encountered
we have been able to resolve in one manner or another. However, here
is one which seems to be a puzzle. We put our elevator on a bench to
do a balance test and found that the elevator was balanced aft the
hinge line to the point that it would require 6 1/2 to 7 pounds of
additional weight at the forward edge of the Ballance horn to create
a balanced state. Normally, it is desired to have neutral to a slight
forward balance state. When we queried Murphy, they said that this
was the design point in all the Murphy Moose kits. So now, our
question is-- did any of you check your balance point before you
installed the elevator, and if so, what was your balance condition?
When we checked back against the original elevator installation
drawings, we realized that our weights are installed in a somewhat
different location than what's called out in the drawings. If anyone
out there also has the weights in their possession before they've
been installed, would you weigh them for us and also take a picture
of their configuration.
It may be that this is not a problem, if it's true that all of
airplanes have been built and flown in this balance state. However,
from the standpoint of flutter, this is a very undesirable
configuration. This is our concern, that somehow we have a unique or
unusual situation.
We will be consulting with Murphy on this, but so far have not
received much useful information.
Blue skies and all the best,
Bob Tripp
Message 2
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | elevator balance |
Hi Bob,
My friend and I rare also building a Moose. Here in Kelowna BC Canada.
We do have the exact situation as you encountering, regarding the
balance weight of the elevator. So far we could not figure out what to
do.
It would be very helpful, if you would let us know, if you come to a
resolution of this problem. As you know, communication with Murphy is
not the easiest thing now a days.
Thank you for posting. And thanks in advance for keeping us posted.
Best Regards,
Peter Cattoni
-----Original Message-----
From: owner-murphymoose-list-server@matronics.com
[mailto:owner-murphymoose-list-server@matronics.com] On Behalf Of BOB
TRIPP
Sent: Tuesday, October 21, 2008 7:46 AM
Subject: MurphyMoose-List: elevator balance
We are in the final stages of assembling our MYSTERIOUS MOOSE at a
hangar in Arlington Airport. Most of the problems we have encountered we
have been able to resolve in one manner or another. However, here is one
which seems to be a puzzle. We put our elevator on a bench to do a
balance test and found that the elevator was balanced aft the hinge line
to the point that it would require 6 1/2 to 7 pounds of additional
weight at the forward edge of the Ballance horn to create a balanced
state. Normally, it is desired to have neutral to a slight forward
balance state. When we queried Murphy, they said that this was the
design point in all the Murphy Moose kits. So now, our question is-- did
any of you check your balance point before you installed the elevator,
and if so, what was your balance condition?
When we checked back against the original elevator installation
drawings, we realized that our weights are installed in a somewhat
different location than what's called out in the drawings. If anyone out
there also has the weights in their possession before they've been
installed, would you weigh them for us and also take a picture of their
configuration.
It may be that this is not a problem, if it's true that all of airplanes
have been built and flown in this balance state. However, from the
standpoint of flutter, this is a very undesirable configuration. This is
our concern, that somehow we have a unique or unusual situation.
We will be consulting with Murphy on this, but so far have not received
much useful information.
Blue skies and all the best,
Bob Tripp
__________________________________________________
D O T E A S Y - "Join the web hosting revolution!"
http://www.doteasy.com
Message 3
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: elevator balance |
MessageBob and Peter,
The elevators on the Turbine Moose we built were not 100% statically
balanced, we used the weights supplied by Murphy installed per the
manual. Our elevator was not 100% balanced. I personally have flown
that airplane to 150 kts indicated.
I am not an aeronautical engineer....hell, not even sure if I spelled it
right. However, do some poking around other airplanes and you will find
many without statically balanced elevators. Van's RV types (fast) do
have 100% static balance on elevators. My first homebuilt, Midget
Mustang, red-line airspeed was 300 mph, it had no static balance weights
on the elevators. C-172s have weights but they are not 100% balanced.
Keep digging, you'll find many more examples.
Hopefully we can stir up an engineer that can explain why we do or do
not need 100% static balance on the elevator.
Doug
www.ripleyair.com
----- Original Message -----
From: Peter Cattoni
To: murphymoose-list@matronics.com
Sent: Tuesday, October 21, 2008 10:24 AM
Subject: RE: MurphyMoose-List: elevator balance
Hi Bob,
My friend and I rare also building a Moose. Here in Kelowna BC Canada.
We do have the exact situation as you encountering, regarding the
balance weight of the elevator. So far we could not figure out what to
do.
It would be very helpful, if you would let us know, if you come to a
resolution of this problem. As you know, communication with Murphy is
not the easiest thing now a days.
Thank you for posting. And thanks in advance for keeping us posted.
Best Regards,
Peter Cattoni
-----Original Message-----
From: owner-murphymoose-list-server@matronics.com
[mailto:owner-murphymoose-list-server@matronics.com] On Behalf Of BOB
TRIPP
Sent: Tuesday, October 21, 2008 7:46 AM
To: murphymoose-list@matronics.com
Subject: MurphyMoose-List: elevator balance
We are in the final stages of assembling our MYSTERIOUS MOOSE at a
hangar in Arlington Airport. Most of the problems we have encountered we
have been able to resolve in one manner or another. However, here is one
which seems to be a puzzle. We put our elevator on a bench to do a
balance test and found that the elevator was balanced aft the hinge line
to the point that it would require 6 1/2 to 7 pounds of additional
weight at the forward edge of the Ballance horn to create a balanced
state. Normally, it is desired to have neutral to a slight forward
balance state. When we queried Murphy, they said that this was the
design point in all the Murphy Moose kits. So now, our question is-- did
any of you check your balance point before you installed the elevator,
and if so, what was your balance condition?
When we checked back against the original elevator installation
drawings, we realized that our weights are installed in a somewhat
different location than what's called out in the drawings. If anyone out
there also has the weights in their possession before they've been
installed, would you weigh them for us and also take a picture of their
configuration.
It may be that this is not a problem, if it's true that all of
airplanes have been built and flown in this balance state. However, from
the standpoint of flutter, this is a very undesirable configuration.
This is our concern, that somehow we have a unique or unusual situation.
We will be consulting with Murphy on this, but so far have not
received much useful information.
Blue skies and all the best,
Bob Tripp
href="http://www.matronics.com/Navigator?MurphyMoose-List">http://www.m
atronics.com/Navigator?MurphyMoose-List
href="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
__________________________________________________
D O T E A S Y - "Join the web hosting revolution!"
http://www.doteasy.com
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|