X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sat, 06 Dec 2008 22:46:17 -0500 Message-ID: X-Original-Return-Path: Received: from QMTA08.emeryville.ca.mail.comcast.net ([76.96.30.80] verified) by logan.com (CommuniGate Pro SMTP 5.2.10) with ESMTP id 3333058 for lml@lancaironline.net; Fri, 05 Dec 2008 15:30:07 -0500 Received-SPF: pass receiver=logan.com; client-ip=76.96.30.80; envelope-from=j.hafen@comcast.net Received: from OMTA10.emeryville.ca.mail.comcast.net ([76.96.30.28]) by QMTA08.emeryville.ca.mail.comcast.net with comcast id nPRZ1a00C0cQ2SLA8YVVVL; Fri, 05 Dec 2008 20:29:29 +0000 Received: from [10.128.90.197] ([76.121.106.8]) by OMTA10.emeryville.ca.mail.comcast.net with comcast id nYVH1a00D0Atgzw8WYVNJk; Fri, 05 Dec 2008 20:29:27 +0000 X-Authority-Analysis: v=1.0 c=1 a=qRa-X-PsrQUA:10 a=bJr6Lm2eytsA:10 a=Ia-xEzejAAAA:8 a=3oc9M9_CAAAA:8 a=Vm88T7o5eTPEXtezfrIA:9 a=djHIs-J1vjmBYLITvowA:7 a=SZ6tYVQxuKBgbG5qAA37pAu3qP0A:4 a=EzXvWhQp4_cA:10 a=U8Ie8EnqySEA:10 a=gi0PWCVxevcA:10 a=G2AsRb49nnwmWARIy9zzNStElGQ=:19 a=dza3k1T56YEQADokn0kA:9 a=rY_sxSMOVboyUWVv85EA:7 a=zwpRWeT-XJ0bfPkelxtFzAK8bB0A:4 a=Sz-0p1zU2dQA:10 User-Agent: Microsoft-Entourage/12.14.0.081024 X-Original-Date: Fri, 05 Dec 2008 12:29:15 -0800 Subject: Re: [LML] Re: outback gear doors-vibration is back From: John Hafen X-Original-To: Lancair Mailing List X-Original-Message-ID: Thread-Topic: [LML] Re: outback gear doors-vibration is back Thread-Index: AclXGCPn6hpJvKFFn06UQTJy27J9zQ== In-Reply-To: Mime-version: 1.0 Content-type: multipart/alternative; boundary="B_3311324964_688636" > This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --B_3311324964_688636 Content-type: text/plain; charset="ISO-8859-1" Content-transfer-encoding: quoted-printable I had the same kind of speed induced noise in my IVP. I corrected it by actually latching the baggage door before takeoff. John Hafen N413AJ 100 hours=20 On 12/5/08 9:06 AM, "Dominic V. Crain" wrote: > I would think that the gear doors rumbling would be far more musical than > listening to AC-DC. > =20 > Cheers > Dom > VH-CZJ > =20 >=20 > From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of > mquinns@aol.com > Sent: Friday, 5 December 2008 3:25 PM > To: lml@lancaironline.net > Subject: [LML] Re: outback gear doors-vibration is back > =20 > Gerard, > I had the same problem. Whenever the airspeed started moving past 210 = knots > a buzz would start and then turn into a rumble as the plane went faster. = If > the aircraft was decelerated......to a speed around 205 knots, the rumbli= ng > and buzzing would disappear but would reappear if the aircraft accelerate= d > back above 210 knots. I was certain it was the nose gear door (made from > fiberglass) so I took the advice in archive and fabricated a much stiffer > aluminum door. To my surprise the buzzing and rumbling problem was still = there > over certain speeds.!!!!???!!!! Fortunately for me, I live at at a place = where > we formation fly to breakfast every Saturday and I usually fly with the S= X-300 > guys. One of these friends volunteered to go up with me and formate under= me > to see if the problem could be observed. Apparently, the main gear doors > trailing edges are being sucked out into the slipstream at certain airspe= eds. > We repeated the speed runs (accelerate/decelerate) and proble! m was clea= r. > My plane does have a difference with yours which is, even though I hav= e the > outback gear, I decided to use the original cutout doors thinking they wo= uld > create less drag. Don't know whether they do or not but have been unable = after > many different attempts to keep the doors closed at high speed. In Januar= y I > will be racing and afterwards plan on doing a major condition inspection > (demating wings, removing all control surfaces, etc) and at that time wil= l fit > the original outback gear doors from the option kit. They do appear to be > stiffer (I hope they don't generate more drag). I hope that this cures my > problem. Some of the Reno racers have recommended stiffening gear doors > because this is a common problem for them while racing. If you find a mag= ic > bullet to correct the problem, please post it. >=20 > Mark Quinn > Lancair 360 > Spruce Creek Fly-in, Florida >=20 >=20 > -----Original Message----- > From: gerardoconnell@optusnet.com.au > To: lml@lancaironline.net > Sent: Wed, 3 Dec 2008 9:15 pm > Subject: [LML] outback gear doors-vibration is back > =20 > =20 > Hi Ian and those whom have had gear door problems > =20 > -Gerard from Down Under/Up Over has gremlins again > =20 > =20 > Hope you're going well and enjoying you're flying. I'm just writing a qui= ck > note=20 > both on and off list as we've been over this ground before. > =20 > Do you recall discussing the buzzing noise I had some time back which I > resolved=20 > both by removing the nose gear door and overlapping the main and inboard = gear > doors to get better "purchase" and stop vibration. > =20 > Well guess what? Thhe noise is now starting to return-I initially thoug= ht I > had the bass turned up too much whilst listening to AC -DC but even with = the > radio off I can appreciate the buzz from outside the aircraft. > =20 > Perhaps I need to listen to Robbie Williams instead? > =20 > I originally spent thousands of $ trying various solutions to this proble= m and > the final fix has worked for about 200 hours. I understand that some have= also > extended the door hinge/bracket to address this problem. > =20 > In short, my question is this-did you have this buzzing/vibration problem= and > what methods did you employ before removing the inner gear doors altogeth= er? > Is=20 > this my best short cut to making the problem go away once and for all? > =20 > Your thoughts would be appreciated including and issues you mar or may no= pt > have=20 > experienced after removing the inner doors. > =20 > =20 > Cheers, > =20 > Gerard > =20 > =20 > =20 > =20 > =20 > -- > For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.ht= ml > =20 >=20 >=20 > Listen to 350+ music, sports, & news radio stations =AD including songs for= the > holidays =AD FREE while you browse. Start Listening Now > = ! >=20 --B_3311324964_688636 Content-type: text/html; charset="ISO-8859-1" Content-transfer-encoding: quoted-printable Re: [LML] Re: outback gear doors-vibration is back I had the same kind of speed induced noise in my IVP.

I corrected it by actually latching the baggage door before takeoff.

John Hafen
N413AJ 100 hours


On 12/5/08 9:06 AM, "Dominic V. Crain" <domcrain@tpg.com.au> wrote:

<= FONT COLOR=3D"#1F497D">I would think that the gea= r doors rumbling would be far more musical than listening to AC-DC.
 
Cheers
Dom
VH-CZJ
 

From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf O= f mquinns@aol.com
Sent: Friday, 5 December 2008 3:25 PM
To: lml@lancaironline.net
Subject: [LML] Re: outback gear doors-vibration is back
Gerard,
   I had the same problem. Whenever the airspeed started mov= ing past 210 knots a buzz would start and then turn into a rumble as the pla= ne went faster. If the aircraft was decelerated......to a speed around 205 k= nots, the rumbling and buzzing would disappear but would reappear if the air= craft accelerated back above 210 knots. I was certain it was the nose gear d= oor (made from fiberglass) so I took the advice in archive and fabricated a = much stiffer aluminum door. To my surprise the buzzing and rumbling problem = was still there over certain speeds.!!!!???!!!! Fortunately for me, I live a= t at a place where we formation fly to breakfast every Saturday and I usuall= y fly with the SX-300 guys. One of these friends volunteered to go up with m= e and formate under me to see if the problem could be observed. Apparently, = the main gear doors trailing edges are being sucked out into the slipstream = at certain airspeeds. We repeated the speed runs (accelerate/decelerate) and= proble! m was clear.
   My plane does have a difference with yours which is, even= though I have the outback gear, I decided to use the original cutout doors = thinking they would create less drag. Don't know whether they do or not but = have been unable after many different attempts to keep the doors closed at h= igh speed. In January I will be racing and afterwards plan on doing a major = condition inspection (demating wings, removing all control surfaces, etc) an= d at that time will fit the original outback gear doors from the option kit.= They do appear to be stiffer (I hope they don't generate more drag). I hope= that this cures my problem. Some of the Reno racers have recommended stiffe= ning gear doors because this is a common problem for them while racing. If y= ou find a magic bullet to correct the problem, please post it.

Mark Quinn
Lancair 360
Spruce Creek Fly-in, Florida


-----Original Message-----
From: gerardoconnell@optusnet.com.= au
To: lml@lancaironline.net
Sent: Wed, 3 Dec 2008 9:15 pm
Subject: [LML] outback gear doors-vibration is back
 
Hi Ian and those whom have had gear door problems
 
-Gerard from Down Under/Up Over has gremlins again
 
 
Hope you're going well and enjoying you're flying. I'm just writing a quick= note
both on and off list as we've been over this ground before.
 
Do you recall discussing the buzzing noise I had some time back which I res= olved
both by removing the nose gear door and overlapping the main and inboard ge= ar
doors to get better "purchase" and stop vibration.
 
Well guess what?   Thhe noise is now starting to return-I initial= ly thought I
had the bass turned up too much whilst listening to AC -DC but even with th= e
radio off I can appreciate the buzz from outside the aircraft.
 
Perhaps I need to listen to Robbie Williams instead?
 
I originally spent thousands of $ trying various solutions to this problem = and
the final fix has worked for about 200 hours. I understand that some have a= lso
extended the door hinge/bracket to address this problem.
 
In short, my question is this-did you have this buzzing/vibration problem a= nd
what methods did you employ before removing the inner gear doors altogether= ? Is
this my best short cut to making the problem go away once and for all?
 
Your thoughts would be appreciated including and issues you mar or may nopt= have
experienced after removing the inner doors.
 
 
Cheers,
 
Gerard
 
 
 
 
 
--
For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.html
=20


Listen to 350+ music, sports, & news radio stations – including = songs for the holidays – FREE while you browse. Start Listening Now &l= t;http://toolbar.aol.com/aolradio/download.html?ncid=3Demlweusdown0000000= 6> !

--B_3311324964_688636--