Today's Message Index:
----------------------
1. 01:05 AM - Re: Extension of outboard Tailplane pip pin holes? (Carl Pattinson)
2. 01:41 AM - Re: Wikipedia's entry on flutter (William Harrison)
3. 03:41 AM - Re: glide ratio (David Joyce)
4. 03:43 AM - Re: Fuel selector valve location (David Joyce)
5. 06:15 AM - Re: Wikipedia's entry on flutter (Jos Okhuijsen)
6. 07:02 AM - Re: Wikipedia's entry on flutter (Carl Pattinson)
7. 07:36 AM - Re: Wikipedia's entry on flutter (William Harrison)
8. 08:06 AM - Re: Wikipedia's entry on flutter (William Harrison)
9. 09:57 AM - Re: Wikipedia's entry on flutter (Jos Okhuijsen)
10. 10:06 AM - Re: Re: EUROPA PIP-PIN RECESS (karelvranken)
11. 10:30 AM - Tailplane flutter & trim (Mark Burton)
12. 11:49 AM - Re: Tailplane flutter & trim (Mike Parkin)
13. 12:17 PM - Re: Tailplane flutter & trim (Mark Burton)
14. 12:59 PM - Tailplane flutter & trim (rlborger)
15. 01:44 PM - VNE Test Question (MJKTuck@cs.com)
16. 02:03 PM - Tailplane Torque Tube (Fred Klein)
17. 03:03 PM - [ Bob Harrison ] : New Email List Photo Share Available! (Email List Photo Shares)
18. 03:11 PM - [ Miles McCallum ] : New Email List Photo Share Available! (Email List Photo Shares)
19. 05:31 PM - Re: Wikipedia's entry on flutter (Jos Okhuijsen)
20. 07:40 PM - Europa pip-pin recess (Fergus Kyle)
21. 09:37 PM - N81EU ~ progess (Thomas Scherer)
Message 1
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| Subject: | Re: Extension of outboard Tailplane pip pin holes? |
We removed the tailplane supports from the trailer the day it arrived. We
knew from others that this could cause the TP5 bond to break. They have
always been carried in the back of the car (on blankets).
----- Original Message -----
From: "Karl Heindl" <kheindl@msn.com>
Sent: Friday, June 22, 2007 11:43 PM
Subject: Re: Europa-List: Extension of outboard Tailplane pip pin holes?
>
>
> Carl, I can confirm the trailer aspect. Before first flight I towed my
> Europa for 1000 km on bumpy Canadian roads. At the end of the trip the
> inboard TP5's had worked themselves loose. I pulled them out and rebonded
> them with floxed redux. No problems since then. But those vertical
> supports on the trailer should never be used. I now carry the tailplanes
> in the back of my car.
>
> Karl
>
>
>>From: "Carl Pattinson" <carl@flyers.freeserve.co.uk>
>>To: <europa-list@matronics.com>
>>Subject: Re: Europa-List: Extension of outboard Tailplane pip pin holes?
>>Date: Fri, 22 Jun 2007 22:51:35 +0100
>>
>>Several Europa pilots have commented on the fact that my pip pins are a
>>loose fit in the torque tube and advised I should drill them properly and
>>fit oversize pins. Fortunately I never got round to it which seems to have
>>been a blessing in disguise.
>>
>>Another cause of the sleeves disbonding is transporting the tailplanes on
>>the Europa trailer. This places a direct strain on the TP6 sleeve, much
>>more that caused by flying or taxying over "rough ground".
>>
>>I would suggest that if you trailer the tailplanes on the trailer, regular
>>checks of the TP6 sleeves would be a good idea.
>>
>>Carl Pattinson
>>G-LABS
>>
>>
>> ----- Original Message -----
>> From: Ron Jones
>> To: europa-list@matronics.com
>> Sent: Friday, June 22, 2007 9:58 PM
>> Subject: Re: Europa-List: Extension of outboard Tailplane pip pin
>> holes?
>>
>>
>> Hi Bob,
>> Slotting the pip-pin holes in the torque tube was recommended to me by
>> Neville - in the presence of Ivan and Andy. It makes good sense and I
>> slotted mine about 1 mm in each direction. Thank goodness, I have no free
>> play anywhere but my pip-pin recesses are non-standard (but IMHO, much
>> better!)
>> Regards,
>> Ron Jones.
>> G-RJWX (XS 359)
>>
>>
>>
>
> _________________________________________________________________
> Win tickets to the sold out Live Earth concert!
> http://liveearth.uk.msn.com
>
>
>
Message 2
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| Subject: | Re: Wikipedia's entry on flutter |
We still can't avoid the question: why did this happen WHEN it did?
Mark makes a good point about slop, in any case, slop would normally
built up slowly. David's information about speed seems to rule that
out as a trigger event. Just a thought, but if one of the stabs
became disengaged, for any reason (sideways movement, loss of TP14D
pin - secured by a single small split pin) from the TP12/13 drive
flange, presumably the other stab would instantly be countering all
of the mass in the TP19 weights, thereby creating a sudden and huge
mass imbalance - enough to cause catastrophic flutter?
Willie
On 22 Jun 2007, at 17:55, David Joyce wrote:
> <davidjoyce@doctors.org.uk>
>
> William, At the PFA today I was told that the radar trace of
> William's plane
> showed it was going at 90 knots or so. He would have done his Vne dive
> somewhere on the way back from Cornwall - all very perplexing.
> Did my Permit renewal test flying today and didn't like
> to ask
> someone to come along as ballast/observer!
> Regards, David Joyce
> ----- Original Message -----
Message 3
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Roger, When my mono with speed kit was new and shiny, I did tests of glide
ratio at different speeds in a big blue gap over the Severn Estuary
(admittedly such air might have bee sinking marginally cutting a little bit
off the true ratio) I found that I had 1:12 at 75 kts with 70 or 80kts
making very little difference. You could argue that choosing 80 adds to your
safety without significant penalty, giving a better margin while you are
distracted by all the things you will be sweating over in the next few
minutes. Gliders with a minimal sink speed of 40 or 50 kts will typically
speed up to 60 kts (or greater in strong winds) to land to have spare energy
in hand to cope with loss of speed going through the wind gradient , etc.
Regards, David Joyce
----- Original Message -----
From: "roger cullum" <rsc-93@hotmail.co.uk>
Sent: Friday, June 22, 2007 11:04 PM
Subject: RE: Europa-List: glide ratio
>
>
> >From: "Jerry Rehn" <rehn@rockisland.com>
> >To: <europa-list@matronics.com>
> >Subject: Europa-List: glide ratio
> >Date: Fri, 22 Jun 2007 11:22:37 -0700
> >
> >Is there an average glide ratio for the Europa based on an average of
> >reports? Prop stopped and prop at idle? Thanks
> >
> >
> >hi jerry,
> i seem to recall seeing approx 500ft /min rate of descent at 75 knots best
> glide speed clean when i was doing my conversion training with prop at
idle
> which equates to approx 15:1 in trigear G-OGAN ,bit better than the cessna
i
> fly at the moment.
> best
> regards andy cullum rebuilding/ converting to trigear G-CGDH
> >Jerry
> >
>
> _________________________________________________________________
> Tell MSN about your most memorable emails! http://www.emailbritain.co.uk/
>
>
Message 4
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| Subject: | Re: Fuel selector valve location |
Fred, It works well where it is - doesn't get knocked inadvertently or
mistaken for anything else. Regards, David Joyce
----- Original Message -----
From: "Fred Klein" <fklein@orcasonline.com>
Sent: Friday, June 22, 2007 11:46 PM
Subject: Europa-List: Fuel selector valve location
>
> The ergonomics of the location of the fuel selector as called for in
> the manual seem to be less than optimal.
>
> I'm wondering if anyone has changed its location(?)...say to the top of
> the tunnel where viewing it and manipulating it might be better.
>
> Or have others investigated this and its impact on other systems and
> decided to let well enough alone?
>
> Fred
> A194
>
>
> --
> This message has been scanned for viruses and
> dangerous content by MailScanner, and is
> believed to be clean.
>
>
Message 5
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| Subject: | Re: Wikipedia's entry on flutter |
Hi William H.
> We still can't avoid the question: why did this happen WHEN it did? Mark
> makes a good point about slop, in any case, slop would normally built up
> slowly. David's information about speed seems to rule that out as a
> trigger event. Just a thought, but if one of the stabs became
> disengaged, for any reason (sideways movement, loss of TP14D pin -
> secured by a single small split pin) from the TP12/13 drive flange,
> presumably the other stab would instantly be countering all of the mass
> in the TP19 weights, thereby creating a sudden and huge mass imbalance -
> enough to cause catastrophic flutter?
Somebody from the UK told me once: We are like mushrooms. We are kept in
the dark, and once in a while we are allowed to see the light, and
somebody throws shit at us. In this case i get the same feeling.
Talking to Graham last night, we decided that at 90 knots there is very
little chance of flutter. But the load on the tailplane is minimal at that
speed. Now, if TP6 was loose, this was the time for the tail plane to move
out wards, disengage from the TP 12 pins and turn square to the direction
of flight, and so destroy itself, shake a wing loose and destroy the
plane. Not necessarily in that order. But as said,we are kept in the dark
and so on, so this is just another speculation.
Regards,
Jos Okhuijsen
http://www.europaowners.org/kit600
Message 6
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| Subject: | Re: Wikipedia's entry on flutter |
It isnt a matter of keeping people in the dark but of arriving at the
correct conclusion. IMHO it is far better to say nothing than to arrive at a
flawed judgement.
And as for this being a British phenomenon what sparked off Tony Blairs war
on Iraq. The assumption that they had WMD with little or no evidence to back
it up. OK, sorry for getting political.
It is to be commended that the PFA have responded so quickly to this
situation and I doubt very much if the answer is as clear cut as people may
wish. At the moment their priority is to prevent a recurrence of this tragic
accident even if it means barking up a few wrong trees. When they have had
the opportunity to fully consider the evidence I am sure we will be amongst
the first to hear.
Purely on the speculation that one of the tailplanes may have moved outboard
and disengaged the drive pins it is a possibility. However I think it highly
unlikely that the disengaged tailplane could have "turned square" as has
been suggested. If you consider the area of tailplane foreward of the torque
tube as compared with the area behind, air pressure would keep the tailplane
in line with the aircraft. I suspect that once disengaged from the drive
pins the unrestrained tailplane would start to oscillate and then flutter.
What effect this disengagement would have on the remaining tailplane is hard
to predict. True there would now be an imbalance in the tailplane assembly
but any force exerted by the mass balance arm could be counteracted by force
applied to the control column. Have you never sat in the plane withouthe
tailplanes connected and moved the stick back and forth. It is heavy but not
impossible to move.
As for it being unlikely that flutter would occur at 90kts my understanding
is that flutter can happen at any speed. What speed does it take to cause
flags to flutter in the wind 10-20knots (even less).
I believe that if there had been a straightford and simple explanation, we
would have heard by now. It is in nobodys interests to keep us in the dark.
----- Original Message -----
From: "Jos Okhuijsen" <josok-e@ukolo.fi>
Sent: Saturday, June 23, 2007 2:13 PM
Subject: Re: Europa-List: Wikipedia's entry on flutter
>
> Hi William H.
>
>> We still can't avoid the question: why did this happen WHEN it did? Mark
>> makes a good point about slop, in any case, slop would normally built up
>> slowly. David's information about speed seems to rule that out as a
>> trigger event. Just a thought, but if one of the stabs became
>> disengaged, for any reason (sideways movement, loss of TP14D pin -
>> secured by a single small split pin) from the TP12/13 drive flange,
>> presumably the other stab would instantly be countering all of the mass
>> in the TP19 weights, thereby creating a sudden and huge mass imbalance -
>> enough to cause catastrophic flutter?
>
> Somebody from the UK told me once: We are like mushrooms. We are kept in
> the dark, and once in a while we are allowed to see the light, and
> somebody throws shit at us. In this case i get the same feeling.
>
> Talking to Graham last night, we decided that at 90 knots there is very
> little chance of flutter. But the load on the tailplane is minimal at that
> speed. Now, if TP6 was loose, this was the time for the tail plane to move
> out wards, disengage from the TP 12 pins and turn square to the direction
> of flight, and so destroy itself, shake a wing loose and destroy the
> plane. Not necessarily in that order. But as said,we are kept in the dark
> and so on, so this is just another speculation.
>
> Regards,
>
> Jos Okhuijsen
>
> http://www.europaowners.org/kit600
>
>
>
Message 7
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| Subject: | Re: Wikipedia's entry on flutter |
Thanks, Jos, I share your frustration about not knowing the full
story (yet). Even when the immediate safety checks have been done it
will still be something of an act of faith that they will completely
preclude a repetition. I expect we'd all like to know very precisely
what happened before we could have full confidence that any
particular fix will prevent it from happening again. I also expect
that eventually we will reach that level of understanding and can go
back to trusting our beautiful little aeroplanes.
90kts was presumably the ground speed as taken from a radar trace.
Airspeed could easily have been +/- 30kts, maybe more, away from that
figure, given the effect of both wind and a possible steep dive.
Would a stab turn 90 degrees when its centre of pressure would be so
far aft of the torque tube? I would have expected it to continue to
point in roughly the right direction until and unless it came right off.
By the way, the Gasco seminar at Farnborough on 8 August is going to
include a tour of the investigation hangers where they do the
forensic analysis on recent wrecks. I believe that is where G-HOFC is
being examined.
Regards
Willie Harrison
On 23 Jun 2007, at 14:13, Jos Okhuijsen wrote:
>
> Hi William H.
>
>> We still can't avoid the question: why did this happen WHEN it
>> did? Mark makes a good point about slop, in any case, slop would
>> normally built up slowly. David's information about speed seems to
>> rule that out as a trigger event. Just a thought, but if one of
>> the stabs became disengaged, for any reason (sideways movement,
>> loss of TP14D pin - secured by a single small split pin) from the
>> TP12/13 drive flange, presumably the other stab would instantly be
>> countering all of the mass in the TP19 weights, thereby creating a
>> sudden and huge mass imbalance - enough to cause catastrophic
>> flutter?
>
> Somebody from the UK told me once: We are like mushrooms. We are
> kept in the dark, and once in a while we are allowed to see the
> light, and somebody throws shit at us. In this case i get the same
> feeling.
>
> Talking to Graham last night, we decided that at 90 knots there is
> very little chance of flutter. But the load on the tailplane is
> minimal at that speed. Now, if TP6 was loose, this was the time for
> the tail plane to move out wards, disengage from the TP 12 pins and
> turn square to the direction of flight, and so destroy itself,
> shake a wing loose and destroy the plane. Not necessarily in that
> order. But as said,we are kept in the dark and so on, so this is
> just another speculation.
>
> Regards,
>
> Jos Okhuijsen
>
Message 8
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| Subject: | Re: Wikipedia's entry on flutter |
You make some fair points, Carl. I think police detectives call it
the ABC approach: Accept nothing, Believe nobody, Check everything.
I can only agree that it is in our interests that the investigators
take as much time as is needed to get the right answer, even though
that leads to short term anxiety and frustration.
I'm not sure I agree with what you say about stick forces since you
are not just trying to counter the deadweight of the remaining stab
but the dynamic forces from the self excited oscillation which is
drawing enormous energy out out the airflow.
I could imagine either or both of the decoupled stabs fluttering. If
it is true that the tailplane fractured off the fuselage then it
suggests that structural oscillation in the fuselage may have been a
component of the flutter (?like the V-tailed Bonanzas??)
Willie Harrison
On 23 Jun 2007, at 15:01, Carl Pattinson wrote:
> <carl@flyers.freeserve.co.uk>
>
> It isnt a matter of keeping people in the dark but of arriving at
> the correct conclusion. IMHO it is far better to say nothing than
> to arrive at a flawed judgement.
>
> And as for this being a British phenomenon what sparked off Tony
> Blairs war on Iraq. The assumption that they had WMD with little or
> no evidence to back it up. OK, sorry for getting political.
>
> It is to be commended that the PFA have responded so quickly to
> this situation and I doubt very much if the answer is as clear cut
> as people may wish. At the moment their priority is to prevent a
> recurrence of this tragic accident even if it means barking up a
> few wrong trees. When they have had the opportunity to fully
> consider the evidence I am sure we will be amongst the first to hear.
>
> Purely on the speculation that one of the tailplanes may have moved
> outboard and disengaged the drive pins it is a possibility. However
> I think it highly unlikely that the disengaged tailplane could have
> "turned square" as has been suggested. If you consider the area of
> tailplane foreward of the torque tube as compared with the area
> behind, air pressure would keep the tailplane in line with the
> aircraft. I suspect that once disengaged from the drive pins the
> unrestrained tailplane would start to oscillate and then flutter.
>
> What effect this disengagement would have on the remaining
> tailplane is hard to predict. True there would now be an imbalance
> in the tailplane assembly but any force exerted by the mass balance
> arm could be counteracted by force applied to the control column.
> Have you never sat in the plane withouthe tailplanes connected and
> moved the stick back and forth. It is heavy but not impossible to
> move.
>
> As for it being unlikely that flutter would occur at 90kts my
> understanding is that flutter can happen at any speed. What speed
> does it take to cause flags to flutter in the wind 10-20knots (even
> less).
>
> I believe that if there had been a straightford and simple
> explanation, we would have heard by now. It is in nobodys
> interests to keep us in the dark.
>
Message 9
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| Subject: | Re: Wikipedia's entry on flutter |
Hi Carl,
> It isnt a matter of keeping people in the dark but of arriving at the
> correct conclusion. IMHO it is far better to say nothing than to arrive
> at a flawed judgement.
It's that attitude where i am pointing to, IMHO it's better to use all
brains available, feed all the facts and see where the discussion leads.
The change that the right solution is found is certainly not smaller. In a
way that is happening here. Excluding myself, there are some very
knowledgeable folks around here. The problem is that the facs are few and
secondhanded. And we all feel insecure.
> It is to be commended that the PFA have responded so quickly to this
> situation and I doubt very much if the answer is as clear cut as people
> may wish. At the moment their priority is to prevent a recurrence of
> this tragic accident even if it means barking up a few wrong trees. When
> they have had the opportunity to fully consider the evidence I am sure
> we will be amongst the first to hear.
Simply grounding every plane certainly makes the flying a lot safer, no
doubt about it. But it does not affect all Europas outside the UK. One
more reason for openess about what happened.
There are a lot of Europas flying around with sloppy tailplanes. Why did
this happen now and how and what evidence is there is what we would like
to hear. That will not impede the investigation, and maybe prevent
accidents outside the jurisdiction of the PFA.
> Purely on the speculation that one of the tailplanes may have moved
> outboard and disengaged the drive pins it is a possibility. However I
> think it highly unlikely that the disengaged tailplane could have
> "turned square" as has been suggested. If you consider the area of
> tailplane foreward of the torque tube as compared with the area behind,
> air pressure would keep the tailplane in line with the aircraft. I
> suspect that once disengaged from the drive pins the unrestrained
> tailplane would start to oscillate and then flutter.
Could it be that the moment the drive pins disengage the plane will
sharply dive or climb, resulting in the loose tailplane turning square?
> As for it being unlikely that flutter would occur at 90kts my
> understanding is that flutter can happen at any speed. What speed does
> it take to cause flags to flutter in the wind 10-20knots (even less).
Sure, but certainly less likely as close to VNE. The flags will flutter
quit a bit more too.
>
> I believe that if there had been a straightford and simple explanation,
> we would have heard by now. It is in nobodys interests to keep us in
> the dark.
So,let'shave the facts. Conclusions may come later.
Regards,
Jos Okhuijsen
http://www.europaowners.org/kit600
Message 10
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| Subject: | Re: RE: EUROPA PIP-PIN RECESS |
Thanks Graham,
I hope that other big guns start to shoot so that it is heard in the PFA
bureau.
Karel Vranken.
----- Original Message -----
From: "Graham Singleton" <grahamsingleton@btinternet.com>
Sent: Saturday, June 23, 2007 12:48 AM
Subject: Re: Europa-List: RE: EUROPA PIP-PIN RECESS
> <grahamsingleton@btinternet.com>
>
> Karel
> You are right about treating symptoms. I too am still very puzzled about
> the cause of William's accident. There are certainly a lot of Europas
> around with 1/2" of looseness in the tailplanes. This arises from that
> rather unwise requirement to drill the TP 10s through the torque tube and
> the TP4s. imho that is where most of this particular problem starts.
>
> The other problem is the security of the TP6 bush which is required to
> keep the tailplane in place. It can come loose from more than one cause.
> Slop in the TP12 allowing hammering while taxying on rough ground.
> Damage caused during derigging or on the trailer.
> I suspect this unhappy situation is, like most accidents, the result of
> more than one factor combining to produse an accident.
> I do find it incredible that it was possible to pull the wings off at 90
> kts.( But then I haven't done the sums.)
> Graham
>
> karelvranken wrote:
>> <karelvranken@hotmail.com>
>>
>> Nigel,
>> I can follow your explanation except when you write: "What is dangerous
>> is if the taiplanes move outwards allowing them to disconnect the TP10
>> pins." TP10's are nylon tubes. You mean perhaps the pins on the TP12?
>> Others do have the same problem hence the discussions: clamps or taper
>> pins. Finally no definite solution nor mandatory modification. The play
>> measured at trailing edge may not be more then 1/2". Karel Vranken,
>
>
>
Message 11
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| Subject: | Tailplane flutter & trim |
Following on from my last post where I suggested that if tailplane flutter was
likely to occur then surely it would have been reported before now given the fleet
hours. I am not aware of any cases, are you?
So assuming for the moment that tailplane flutter is unlikely to occur when flying
at VNE even when some slop is present in the tailplane system, it begs the
question: why isn't it fluttering?
Well, I don't know about everyone else but when I do the VNE run the trim is set
to a much lower speed and, consequently, I have to push a lot on the stick to
make it go downhill. All that push force is being transmitted to the tailplanes
and so any slop (hypothetical slop, of course!) in the system is taken up.
However, if while at VNE I was so foolish as to start trimming forward, the required
push force would reduce until it became zero (assuming the trimmer has enough
range) and, at that point, the tailplanes could, potentially, start to flutter
due to the slop no longer being taken up by the stick force.
I wonder if a Europa has ever been trimmed out at VNE? Did the factory do that
in their test flying?
I am not going to try the experiment to see what happens.
Perhaps those of you who understand these issues would care to comment?
Mark
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=120236#120236
Message 12
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| Subject: | Re: Tailplane flutter & trim |
Mark,
I think you have some false assumptions in your message. The increase in
forward stick force to maintain the high speed/dive is because more
tailplane 'leading edge up' is required to counter the increase in mainplane
lift - if you don't hold the forward stick pressure, plainly, the nose will
rise. Aircraft decellerates and the required forward stick force will
reduce.
It follows then that the required tailforce in high speed flight is the same
whether the aircraft is in trim or not - if the speed and aircraft attitude
are to remain the same. The actual way the tailplane generates the required
force will be slightly different because in one situation the tail is
positioned by a constant control input force, while in the trimmed situation
the force (for want of a better word) is provided by the trim tabs. The
real academic answer is probably too complex for me, but I am sure our
aerodynamicists could enlighten us.
By holding a control force the only slop that is being countered is that
from the cockpit to the torque shaft horn. I think that flutter is an issue
between the aerodynamic centre of pressure, the centre of gravity of the
control surface and its hinge line. I think that slop in the control system
leading back to the tailplane is largely irrelevant.
As far as trimming out the aircraft at high speed, it is a non event - old
habits die hard - and I always fly the aircraft in trim within the
capabilities of the trim system itself. I consider that doing a Vne test
holding a huge forward stick force presents a few problems, not least of
which is the possibility of a PIO developing. It is not the way to fly any
aeroplane.
(my 2 cents worth, for what its worth)
regards,
Mike
Do not archive.
----- Original Message -----
From: "Mark Burton" <markb@ordern.com>
Sent: Saturday, June 23, 2007 6:30 PM
Subject: Europa-List: Tailplane flutter & trim
>
> Following on from my last post where I suggested that if tailplane flutter
> was likely to occur then surely it would have been reported before now
> given the fleet hours. I am not aware of any cases, are you?
>
> So assuming for the moment that tailplane flutter is unlikely to occur
> when flying at VNE even when some slop is present in the tailplane system,
> it begs the question: why isn't it fluttering?
>
> Well, I don't know about everyone else but when I do the VNE run the trim
> is set to a much lower speed and, consequently, I have to push a lot on
> the stick to make it go downhill. All that push force is being transmitted
> to the tailplanes and so any slop (hypothetical slop, of course!) in the
> system is taken up.
>
> However, if while at VNE I was so foolish as to start trimming forward,
> the required push force would reduce until it became zero (assuming the
> trimmer has enough range) and, at that point, the tailplanes could,
> potentially, start to flutter due to the slop no longer being taken up by
> the stick force.
>
> I wonder if a Europa has ever been trimmed out at VNE? Did the factory do
> that in their test flying?
>
> I am not going to try the experiment to see what happens.
>
> Perhaps those of you who understand these issues would care to comment?
>
> Mark
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=120236#120236
>
>
> --
> 15:04
>
>
Message 13
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| Subject: | Re: Tailplane flutter & trim |
Mike,
The way I see it, either the trim tab provides the force or the pilot does through
the stick (or a combination of the two).
If the pilot provides some force, that force goes all the way from the pilot's
hand to the tailplane - all slop will be taken out while the pilot is pushing.
If the trim tab provides the force. The tailplane is "balanced" and so no force
is needed through the control system and the tailplane will "float" compared
to the pilot's hand and all the sloppy parts will clunk about.
Your point about PIOs is good.
Cheers,
Mark
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=120244#120244
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| Subject: | Tailplane flutter & trim |
Fellow Europaphiles,
If the tailplane moves outboard and disconnects from the TP14 pins
something else happens that's very bad. The anti-servo/trim tab
comes free from the control "T" rod. You now have a free-floating
tab hinged on the front edge with CG well back from the hinge. You
now have the perfect setup for a fluttering trim tab. Matter of
fact, it will probably flutter at a much lower speed than you might
expect. Flutter the tab and you are surely going to flutter the
stab. We all know how powerful the stab is. You will have to make
the aircraft get real slow real fast or it's going to come apart.
Maybe you can't even get slow enough to stop it.
Good building and great flying,
Bob Borger
Europa Kit #A221 N914XL, XS Mono, Intercooled 914, Airmaster C/S
http://www.europaowners.org/N914XL
(90%) tail kit done, wings closed, cockpit module installed, pitch
system in, landing gear frame in, rudder system in, outrigger mod in,
Fuselage Top on, lift/drag/flap pins in, wing incidence set, tie bar
in, flap drive in, Mod 70 done. Baggage bay in. Flaps & Main Gear
complete. Mod 72 complete. Instrument panel complete, except for
testing. Rotax 914 installed (for the 3rd time). Airmaster Prop
installed. Electrical complete, except for testing. Fuel system
complete except for testing. Working in - 32 Tail, 34 Door Latches &
35 Doors, 37 Interior & Finishing. Airmaster arrived 29 Sep 05.
Seat arrived from Oregon Aero. E04 interior kit has arrived and is
being installed.
3705 Lynchburg Dr.
Corinth, TX 76208
Home: 940-497-2123
Cel: 817-992-1117
Message 15
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| Subject: | VNE Test Question |
I have been watching the e-mails regarding these tragic circumstances. I for
one will be waiting for the facts of the case before performing any mods
although I have made sure that I have no up/down side to side movement of the
tailplanes. All is solid fortunately. I'm kind of surprised the PFA has issued
'maybe it was this so modify it' bulletins but hopefully a final fact based
solution will be provided soon.
I have a question though ..
VNE is a design speed (presumably calculated) - with some margin maybe?
I was intrigued by the UK requirement to dive to VNE as part of the annual
check. What exactly are you trying to prove by performing this test annually?
How many of your wear parachutes when performing this test?
Regards,
Martin Tuck
Europa N152MT
Wichita, KS
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| Subject: | Tailplane Torque Tube |
Jim,
What with the recent discussion of tailplane issues and my need to
address mis-aligned TP13 bushes, I came across your post in 2006. After
reading resultant posts on your thread, I'm curious how you proceeded
and how you feel about your results. When you mention using a machine
shop to make your holes, does that mean you removed your torque tube
from your completed aircraft in order to do the shop work? What kind of
a job was that?...I didn't realize it was feasible...
Fred
A194
On Monday, October 23, 2006, at 04:05 PM, Jim Butcher wrote:
> Recent inspection has revealed excessive play in our port tailplane.
> The problem is play in the torque tube pin. We incorporated Mod 62
> (larger pins) during our build so that=92s not an option.
>
> Our Tech Counselor suggested using AN386 taper pins. He said they are
> commonly used for similar applications in certificated aircraft. AC
> 43-13 confirms that AN386 pins are used in joints where "the absence
> of play is essential".
>
> A search of this forum suggested that the inner tube (TP4) would crush
> and bind in the bearing (TP11) if tapered pins were used. Our thoughts
> are to Loctite a 12" length of 1.375" OD .093" wall 4130 steel tubing
> centered inside of TP4. This would prevent the crushing of TP4 and 12"
> allows it to span the TP11 bearings. We would use a machine shop to
> accurately make the tapered holes for AN386-3 pins. The tapered pins
> would be installed vertically since there is not much material left on
> TP9 (the center bracket) from the installation of 3/8", Mod 62 pins.
>
> In the original design, the pins also locate TP10 sleeves against TP11
> bearings inside the fuselage to prevent left - right torque tube
> movement. We would like to locate TP10 independently of the pins. Our
> thoughts are to machine TP10 sleeves to fit outside the fuselage
> between TP12 and TP11 to achieve the same purpose. Alternatively, we
> could split or slot TP10 and secure them to TP12 inside the fuselage
> with hose clamps (Oetiker style for 360 deg contact).
>
> Comments?
>
> Jim & Heather Butcher
--
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| Subject: | [ Bob Harrison ] : New Email List Photo Share Available! |
A new Email List Photo Share is available:
Poster: Bob Harrison <ptag.dev@tiscali.co.uk>
Lists: Europa-List
Subject: G-PTAG
http://www.matronics.com/photoshare/ptag.dev@tiscali.co.uk.06.23.2007/index.html
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| Subject: | [ Miles McCallum ] : New Email List Photo Share Available! |
A new Email List Photo Share is available:
Poster: Miles McCallum <milesm@avnet.co.uk>
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Subject: Flyer Europa Taildragger
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| Subject: | Re: Wikipedia's entry on flutter |
Don't know if it's important, and i can't really oversee the implications,
if it's important let somebody please bring it to the attention of the
accident ivestigators. I doubt if they do investigate these archives.
In one of the threads about the tailplane drive the following message has
been written:
-----------------
Posted: Sun Aug 27, 2006 8:04 am Post subject: Re: Mod. 62 -
Replacement of tailplane torque tube drive
The other way is to clean the drive sleeve and torque tube surfaces with
acetone and a jet of compressed air, then use a wicking grade Loctite to
bond them together after lining up the tailplane trailing edges. It must be
about 800 to 900 hours since I did that to mine and they are still solid. I
will, of course, have to deal with dismantling if I ever have to, but a
heat
source inside the torque tube should do the trick. I also had to provide
some lubricating tubes to replace the oil into the torque tube bearings,
because the acetone washes that out too.
Regards,
William
------------------
Regards,
Jos Okhuijsen
http://www.europaowners.org/kit600
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| Subject: | Europa pip-pin recess |
Hello,
I don't quite understand the process of elongating the pip-pin
holes. Mine are tighter'n a drum all round and so they touch everywhere
(presumably), whereas if I were to elongated any, then won't the long side
only be touched tangentially by the pin. Won't this then permit the long
side to be slowly indented, and won't the condition accelerate as the event
(and inner surface) wear on?
What am I missing here?
Happy Landings
Ferg
Wiring, wiring, wiring
Message 21
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Hi All,
I've been quiet and that in part because I have been deeply touched by the
accidents that happened between my incident on Feb 24 and now - and the
Oshkosh accident last year,. All those personally affected and close to
those brethren we lost ~ my deepest condolences.
Like many I am a little puzzled by the advent of 'flutter' and will await
further details. On stalls, spins and 180's I would like to add my 2 cent:
I have done 180's three times in my carreer due to not so welcoming areas
ahead ~ yet in February there was no altitude whatsoever - not even for a
left turn. I went straight ahead and had only one thought in mind: "keep air
over those wings til the end". I flew us into a quary which is right
adjacent to the airport, and that was not a nice prospective ~ but I wanted
to remain in control of the plane til the last moment. It sure did pay off
as we walked away - only the plane was hurt.
I think 180's or partial turns are alright as long as you have the speed and
remain in control. Of spins I am so profoundly afraid that I always keep her
above 75 kn, unless flaps are down and in ground effect. Must say though
that N81EU does not appear to have that pronounced drop of one wing as some
report. No stall strips installed.
I am totally confident in the Europa being of good and sound design - a very
capable airplane.
~~~~~~~~~~~~~~~
Today I want to report that in the last 48 hours N81EU was repainted, doors
re-fitted, engine installed and wings back on.
See a picture of her in the hangar here:
<a href="http://www.flickr.com/photos/tosstudio/607079004/" title="Photo
Sharing"><img
src="http://farm2.static.flickr.com/1089/607079004_a95d230511.jpg"
width="500" height="500" alt="repair12" /></a>
and
<a href="http://www.flickr.com/photos/tosstudio/607078996/" title="Photo
Sharing"><img
src="http://farm2.static.flickr.com/1305/607078996_eccbf1630e_o.jpg"
width="800" height="306" alt="repair11" /></a>
There is still plenty to do, yet I feel that Oshkosh is within reach.
Once first flight (at 980 hrs on the hobbs...) occurs, I will send an eMail
with full story on the cause (fuel starvation) and process of the forced
landing and the repair effort.
be well, fly safely,
<Thomas, N81EU>
BTW - do not install high-compression Xtra pistons. Me and others have not
have had success with them. While you'll admittedly gain power - other
trouble WILL arise.
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