X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 05 Mar 2012 08:21:09 -0500 Message-ID: X-Original-Return-Path: Received: from nm3-vm0.bullet.mail.bf1.yahoo.com ([98.139.212.154] verified) by logan.com (CommuniGate Pro SMTP 5.4.4) with SMTP id 5428268 for lml@lancaironline.net; Sun, 04 Mar 2012 23:16:30 -0500 Received-SPF: none receiver=logan.com; client-ip=98.139.212.154; envelope-from=chris_zavatson@yahoo.com Received: from [98.139.212.147] by nm3.bullet.mail.bf1.yahoo.com with NNFMP; 05 Mar 2012 04:15:54 -0000 Received: from [98.139.212.248] by tm4.bullet.mail.bf1.yahoo.com with NNFMP; 05 Mar 2012 04:15:54 -0000 Received: from [127.0.0.1] by omp1057.mail.bf1.yahoo.com with NNFMP; 05 Mar 2012 04:15:54 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 292607.39495.bm@omp1057.mail.bf1.yahoo.com Received: (qmail 4509 invoked by uid 60001); 5 Mar 2012 04:15:54 -0000 DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=AcVElPnj8iz+ffXKh2vXuMtLQlGhLUYU4gfGKccZMbwkkZAklpJQt6sQHgsgIH/nay6yWnMalk4ZLlXKo9qor+qbAYHygwfMRG/KUZoVvOHjNasG4fbn2Dmov8OxzXsoKoz1i+fLJ8FPoXO7diRjxM9L2/Uo4MxoR22Nj6zTpjE=; X-YMail-OSG: 2ewloxYVM1nrRve6zPqaCXaZiou69Qd.wFWzzxNyiVDCyzV Xic9Tm36kAps8mCnAMGfwkRty5XwxIM435Qq6NEDl3Wp9lLm7KyXncb2gp9G zOEDdbqA51oGBBBQLTNVVCc49WWaNaJ0rvSq3QOZ_lBNFaI18VwbgT5GIS2M IHzyY5tiCk0DZ5FA2sz1G08A6vqy5Idv8j5GjR1Qc1sAe0YaC.U9flvhb6_s _OFmwffo26LUvdYGXgcV0qWh.mwHm2hkRkVNmvkQFG3GzCO7E3XQ2qS4G67B _RI0j6bRYVUDJtfgarw6Hk8o_NLJz1w4h9d1qSSAc9un3k9L6ufOW5F9bWzz BpRFdMXZcqglOo_OnJHtcoA4G_KVlX0Tzp2neIdyEpJgiMb3AAxvN3.PuyWQ Y9tI8JJnapeOPL3hLHstmJNZvWWAqdk2d5UaKWk2PQWWz3oiKyvmqd9A.6X. oUNaDP2Pl7xlgd05.WLVe9iZASrsfgB2f9fye3FSt83nOaP8Bc1Y7WvHCERD LxCksZbw0qZGsaLG8_LgnEBatAOOKvGfTVgP3UmzA9iq2oJx0sg4- Received: from [99.149.12.101] by web160401.mail.bf1.yahoo.com via HTTP; Sun, 04 Mar 2012 20:15:53 PST X-Mailer: YahooMailWebService/0.8.116.338427 References: X-Original-Message-ID: <1330920953.75972.YahooMailNeo@web160401.mail.bf1.yahoo.com> X-Original-Date: Sun, 4 Mar 2012 20:15:53 -0800 (PST) From: Chris Zavatson Reply-To: Chris Zavatson Subject: Re: [LML] Re: 320/360 Hydraulic Pressure Switch X-Original-To: Lancair Mailing List In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-900245849-1967780246-1330920953=:75972" ---900245849-1967780246-1330920953=:75972 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Wolfgang,=0AIf a mechanic were to install a new cylinder on my plane using = incorrect rings that subsequently led to oil consumption of 2 qt/hr, I coul= d theoretically design a system that refills the sump to assure I don=E2=80= =99t run out of oil during long flights.=C2=A0 The more customary approach = would be to remove the cylinder and install the correct rings.=0AThe =E2=80= =98problem=E2=80=99 here is not that oil needs to be replenished.=C2=A0 The= problem is the installation of incorrect parts.=C2=A0 The =E2=80=98fix=E2= =80=99 is not to add a system to keep the sump replenished.=C2=A0 The fix i= s to use the correct rings.=0AChris Zavatson=0AN91CZ=0A360std=0Awww.N91CZ.n= et =0A=C2=A0=0A=C2=A0=0AFrom: Wolfgang =0ATo: lml@lanca= ironline.net =0ASent: Saturday, March 3, 2012 4:01 PM=0ASubject: [LML] Re: = 320/360 Hydraulic Pressure Switch =0A=0A=0A=EF=BB=BF =0AChris,=0A=C2=A0=0AL= ife is complicated enough so when I fly, I like to enjoy it. Being a slave = to the system like a cog in a flying machine is not my idea of "enjoyment".= Don't get me wrong, I like getting into technicals up to my eyebrows, but = I prefer to do that at my choosing, not while tending to a malfunction in f= light. That's why I cane up with the gear module. =0A=C2=A0=0AAfter you det= ailed the presence of springs in the pump to help center the spool and pope= ts, I see that my original supposition that the spool is coming off it's en= d position is confirmed. It looks like the springs are in fact, capable of = overcoming the friction of the O-rings. You keep measuring the forces in G'= s but that does not give us an actual force measurement that is what the sp= rings are operating against. =0A=C2=A0=0AIt remains that some pump installa= tions have the problem of the spool not maintaining the required position f= or safe flight operations. You have come up with many details that go towar= d esplaining the problem and a possible fix (take out the springs). I have = come up with a module that WILL fix that problem.=0A=C2=A0=0AWolfgang=0A=C2= =A0=0A----- Original Message ----- =0A>From: Chris Zavatson =0A>To: lml@lan= caironline.net =0A>Sent: Friday, March 02, 2012 7:54 AM=0A>Subject: [LML] R= e: 320/360 Hydraulic Pressure Switch =0A>=0A>=0A>Wolfgang, =0A>=C2=A0=0A>It= is a sad day when removing a pump from the aircraft is too much effort to = investigate an anomaly.=0A>=C2=A0=0A>Wolfgang wrote:<>=0A>=C2=A0=0A>As aircraft owners we are responsible for knowing = the configuration of the aircraft systems.=C2=A0 If something is=C2=A0out o= f the ordinary, investigate.=C2=A0 We know a lot about what the configurati= on should be and how it works and behaves.=C2=A0 We also know of configurat= ions that do not work.=C2=A0 You may=C2=A0very well be holding the key to a= =C2=A0new, as of yet, unidentified failure mode, but we=C2=A0may never know= .=0A>=C2=A0=0A>Wolfgang wrote:<>=0A>=C2=A0=0A>If my tire has a flat an= d I see a nail sticking through the side wall, I am rather confident in ass= uming the nail was the source of my leak.=C2=A0 Likewise, if I open up a lo= ck-up prone pump and find return springs, I will have a high degree of conf= idence I have found the source of the problem.=C2=A0 Could there be a secon= d cause?=C2=A0 Possibly, but as of yet, none have been documented.=0A>=C2= =A0=0A>Wolfgang wrote:<<=E2=80=A6original suspicion of the spool coming off= it's end point (with the help of springs and airframe vibration) is in fac= t what's causing the problem.>>=0A>=C2=A0=0A>Springs definitely - that is w= hat they were designed to do. =C2=A0Oildyne started adding springs to cente= r the spool to the Legacy pump in ~2003.=C2=A0 Our system will eventually f= ail if these springs are installed. Fortunately the vast majority of our pu= mps=C2=A0do not have them.=C2=A0=C2=A0If you have springs installed, simply= remove them.=0A>=C2=A0=0A>Vibration - the evidence says otherwise.=C2=A0 M= easurements of various spool and pump combinations=C2=A0required from 13 g'= s=C2=A0(9 year old 'soft' o-ring) to 70 g's (new 'stiff' o-ring)=C2=A0to mo= ve the spool.=C2=A0 Aircraft vibration at the pump was measured to be +/- 0= .1 g (flying) to +/-1.3 g (engine start). Vibration=C2=A0is not nearly=C2= =A0sufficient to have any effect on the spool.=C2=A0=0A>=C2=A0=0A>Wolfgang = wrote:<>=0A>The springs are very strong, 26 lb/in.=0A>=C2=A0=0A>Wolfgang wrot= e:<>=0A>See MIL-STD-810 for expected vi= bration levels in aircraft environments.=0A>=C2=A0=C2=A0=0A>Wolfgang wrote:= <>=0A>I would still like to kno= w how push buttons can overload anything.=C2=A0=C2=A0And why would anyone w= ant to override more than one at a time?=0A>=C2=A0=0A>Wolfgang wrote:<=0A>I have never had a ther= mal lock up, yet I use pressure gauges and the momentary push buttons on a = regular basis.=C2=A0 They were originally installed to deal with sticking V= EP switches, but it is like getting a new tool.=C2=A0 After you have it, yo= u can't imagine how you lived without out it.=C2=A0 I have already discusse= d the benefits of momentary switches not related to hydraulic lock-up.=0A>= =C2=A0=0A>Wolfgang wrote:<>=0A>One should label=C2=A0the push buttons appr= opriately.=0A>=C2=A0=0A>Wolfgang wrote:<S= prings that are not documented in the Oildyne spec sheet ?>>=0A>Recall that= the Legacy pump configuration =E2=80=9CCZZ=E2=80=9D is proprietary to Lanc= air.=C2=A0 Companies generally don=E2=80=99t post proprietary materials on-= line.=0A>=C2=A0=0A><>=0A>Not really.=C2=A0 I avoid them by thorough examination, no mat= ter what it requires.=0A>=C2=A0=0A>Chris Zavatson=0A>N91CZ=0A>360std=0A>www= .N91CZ.net=0A>=C2=A0=0A>=C2=A0 ---900245849-1967780246-1330920953=:75972 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Wolfgang,
If a mechanic were to install a new cyli= nder on my plane using incorrect rings that subsequently led to oil consump= tion of 2 qt/hr, I could theoretically design a system that refills the sum= p to assure I don=E2=80=99t run out of oil during long flights.  The more customary approa= ch would be to remove the cylinder and install the correct rings.
The =E2=80=98problem=E2=80=99 here is no= t that oil needs to be replenished. = The problem is the installation of incorrect parts.  The =E2=80=98fix=E2=80=99 is not to add a s= ystem to keep the sump replenished. = The fix is to use the correct rings.
Chris Zavatson
N91CZ
360std
www.N91= CZ.net
 
 
From:= Wolfgang <Wolfgang@MiCom.net>
To: lml@lancaironline.net
Sent: Saturday, March 3, 2012 4:01 PM
Subject: [LML] Re: 320/360 Hydraul= ic Pressure Switch

=EF=BB=BF=20
Chris,
 
Life is complicated = enough so when I fly, I like to enjoy it. Being a slave to the system like = a cog in a flying machine is not my idea of "enjoyment". Don't get me wrong= , I like getting into technicals up to my eyebrows, but I prefer to do that= at my choosing, not while tending to a malfunction in flight. That's why I= cane up with the gear module.
 
After you detailed t= he presence of springs in the pump to help center the spool and popets, I s= ee that my original supposition that the spool is coming off it's end posit= ion is confirmed. It looks like the springs are in fact, capable of overcom= ing the friction of the O-rings. You keep measuring the forces in G's but t= hat does not give us an actual force measurement that is what the springs a= re operating against.
 
It remains that some= pump installations have the problem of the spool not maintaining the requi= red position for safe flight operations. You have come up with many details= that go toward esplaining the problem and a possible fix (take out the spr= ings). I have come up with a module that WILL fix that problem.
 
Wolfgang
 
----- Original Message -----
Sent: Friday, March 02, 2012 7:54 AM=
Subject: [LML]= Re: 320/360 Hydraulic Pressure Switch

Wolfgang,
 
It is a sad day when removing a p= ump from the aircraft is too much effort to investigate an anomaly.<= I>
 
Wolfgang wrote:<<= We would all like to get at the root cause of the problem but, as yet, that= hasn't happened. Likely because it's too much work to track down the actua= l cause and fix it. =E2=80=A6>>
 
As aircraft owners we are respons= ible for knowing the configuration of the aircraft systems.  If someth= ing is out of the ordinary, investigate.  We know a lot about wha= t the configuration should be and how it works and behaves.  We also know of configurations that do not work.  You= may very well be holding the key to a new, as of yet, unidentifi= ed failure mode, but we may never know.
 
Wolfgang wrote:<= /I> <<So fa= r we only have a good plausible theory missing only demonstratable proof.&g= t;>
 
If my tire has a flat and I see a nail sticking= through the side wall, I am rather confident in assuming the nail was the = source of my leak.  Likewise, if I open up a lock-up pron= e pump and find return springs, I will have a high degree of confidence I h= ave found the source of the problem.  Could there be a se= cond cause?  Possibly, but as of yet, none have been documented.
 
Wolfgang = wrote:<<=E2=80=A6original suspicion of the spool coming off it's end = point (with the help of springs and airframe vibration) is in fact what's c= ausing the problem.>>
 
Springs definitely - that is what= they were designed to do.  Oildyne started adding spring= s to center the spool to the Legacy pump in ~2003.  Our s= ystem will eventually fail if these springs are installed. Fortunately the = vast majority of our pumps do not have them.  If you have sp= rings installed, simply remove them.
 
Vibration - the evidence says oth= erwise.  Measurements of various spool and pump combinations requ= ired from 13 g's (9 year old 'soft' o-ring) to 70 g's (new 'stiff' o-r= ing) to move the spool.  Aircraft vibration at the pump was measu= red to be +/- 0.1 g (flying) to +/-1.3 g (engine start). Vibration is = not nearly sufficient to have any effect on the spool. 
 
Wolfgang = wrote:<<If it takes that much force to move the spindle against the O= -rings then those springs must be pretty darn strong. I find that dificult = to accept.>>
The springs are very strong, 26 l= b/in.
 
Wolfgang = wrote:<<Vibration levels can exceed = 70 G's>>
See MIL-STD-810 for expected vibr= ation levels in aircraft environments.
  
Wolfgang = wrote:<<Yes, that would be easy . . . except . . . you can only overr= ide one pressure switch at a time or overload the system>>=
I would still like to know how pu= sh buttons can overload anything.  And why would anyone want to o= verride more than one at a time?
 
Wolfgang = wrote:<<The items you cited are more a one-of condition ...>
I have never had a thermal lock up, yet I use = pressure gauges and the momentary push buttons on a regular basis.  Th= ey were originally installed to deal with sticking VEP switches, but it is = like getting a new tool.  After you have it, you can't imagine how you= lived without out it.  I have already discussed the benefits of momen= tary switches not related to hydraulic lock-up.
 
Wolfgang wrote:<<In the event of a pro= blem you have to make sure you push the right switch.>>
One should label the push buttons appropr= iately.
 
Wolfgang wrote:<<Are you saying that O= ildyne is putting springs in the spool to center it when the pump is not ru= nning ?
Springs that are not documented in the Oildy= ne spec sheet ?>>
Recall that the Legacy pump configuration =E2= =80=9CCZZ=E2=80=9D is proprietary to Lancair.  Companies = generally don=E2=80=99t post proprietary materials on-line.
 
<<You seem to want to be "involved" i= n the anomalies of flight.>>
Not really.  I avoid them by= thorough examination, no matter what it requires.
 
Chris Zavatson
N91CZ
360std
 
 


---900245849-1967780246-1330920953=:75972--