X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.121] verified) by logan.com (CommuniGate Pro SMTP 5.2.9) with ESMTP id 3231125 for flyrotary@lancaironline.net; Mon, 20 Oct 2008 15:16:45 -0400 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.121; envelope-from=eanderson@carolina.rr.com Received: from computername ([75.191.186.236]) by cdptpa-omta02.mail.rr.com with ESMTP id <20081020191610.ZTSL2525.cdptpa-omta02.mail.rr.com@computername> for ; Mon, 20 Oct 2008 19:16:10 +0000 From: "Ed Anderson" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Water in the fuel? Date: Mon, 20 Oct 2008 15:16:15 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_001F_01C932C6.CBEED470" X-Mailer: Microsoft Office Outlook, Build 11.0.5510 Thread-Index: AckyxwKV/Ro0yjcAQYCNzOHLd3Yi5AAIQhvg X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 In-reply-to: Message-Id: <20081020191610.ZTSL2525.cdptpa-omta02.mail.rr.com@computername> This is a multi-part message in MIME format. ------=_NextPart_000_001F_01C932C6.CBEED470 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Good point, Lynn. If I had a bit better presence of mind, I would have checked the air/Fuel ratio indicator to see if it went lean when the = engine stumbled. But, alas, I simply can=92t seem to remain sufficiently = detached from the situation at hand when the engine is dying - to study secondary effects{:>) =20 Ed =20 Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com http://www.andersonee.com http://members.cox.net/rogersda/rotary/configs.htm#N494BW http://www.dmack.net/mazda/index.html _____ =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Lynn Hanover Sent: Monday, October 20, 2008 11:17 AM To: Rotary motors in aircraft Subject: [FlyRotary] Water in the fuel? =20 I always like to share happy little "incidents" with others on the list = in hopes we all might benefit =96 not just me {:>). I landed at Shady Bend none-stop from NC with the left tank empty and 14.7 gallons in the right tank. =20 =20 On the way returning from the Rotary Round up at Shady bend; I stopped = to refuel at WayCross, GA as I normally do. Everything thing has been work outstandingly on the trip thus far. =20 I took off and got up to my intended cruise of 5500 MSL (30 kt headwind there, but bumpy as heck any lower). With such a headwind, I knew the flight would be uneventful (the incidents happen when I have a tail = wind). After about 30 minutes I decided to switch from my right wing tank to my left. So I turned on the boost pump and both high pressure pumps and = turned the fuel selector switch to the left tank. =20 Normally there is a non-event, there is no hiccup or hesitation =96 = normally! Well this time things were different, the engine started to surge - big time =96 as did my heart. The fuel pressure is wiggling a small amount = but clearly with pressure above 35 psi it is adequate.=20 =20 My mind races back to that incident a long time ago where I glided 12 = miles engine out =96 and I decided there was no benefit to be gained by = repeating that experience. So as I rapidly raced cause and solution hypothesis through my head, I reached over and turned on the cold start switch. = The engine began to run almost normally, I switched cold start off and the = surge returned. I hit "nearest" on my Garmin and turned toward the nearest airport (17 miles). Then back to the engine. It is still surging = although not quite as badly as it had been =96 but still way too much to be = comfortable with =96 and that fuel pressure is still nominally around 40 psi. What = goes? =20 I then turned off my secondary injectors - the engine began to run = smoothly (although I don't know if this was more than a coincident of timing). = So recalling my lesson learned from that earlier incident (switch tanks, dummy!), I switched back to the right tank =96 happily every thing = settled down (including my heart) and the engine ran normally. =20 After getting a bit closer to the target airport, I gathered my nerves = (what remained of them) and switched back to the left tank =96 there was a = momentary burble, but then the engine started running normally and did so for the = rest of the flight burning 10 gallons out of that tank. =20 Naturally, I am trying to figure out what could possibility have cause = this momentary hiccup. Here is the best I can come up with. =20 I landed at Shady bend with the left tank with approx =BE gallon in it. = It so happens the gas cap on that tank is in need of an O ring replacement as = I noticed a small amount of fuel streaming from the cap area. Well, the aircraft set outside through a few light rain showers while at Shady = Bend. I believe that water may have seeped through the cap and collected in = the tank. (No, I did not do a drain of my tanks checking for water as I = should have). I used to do it religiously, but after 8 years of so of never finding a single drop of water, I had lapsed in that check. No excuses = =96 just the facts. =20 So if a =BD cup or water or so had gotten into that empty tank, it would naturally have settled at the bottom =96 right next to the fuel pick up. = I refueled at WayCross putting fuel into both tanks =96 no problem with = the right tank (with a non-leaking cap). So I believe that I took off with = some amount of water in the left tank. When I switched fuel tanks that slug = of water was sitting right there waiting to be sucked into the system. = This is why (I believe) the fuel pressure did not go down as it would have if = there had been no liquid being pumped through the system. So it basically = took a few hair raising moments to suck all the water through the system and = into the engine =96 then all was well. =20 I am not certain why hitting the "cold Start" switch would have made any difference, but I did turn it on twice and each time the engine settled down. Also when the secondary injectors were momentarily turned off the engine smoothed out. It may have to do with injecting water into the secondaries (which are positioned further away from the engine) and = perhaps the evaporative effect was sufficient to freeze the water vapor??? = Don't know, but I am convinced that water in the fuel was the most likely = cause. =20 I think the principal point is that had I done the fuel drain according = to Hoyle I would have likely discovered the water and drained it. So once again, a bit red-faced to admit to failing to follow long established check-list procedures (I know none of the rest of you do that), I found = an interesting "incident" to relate to the list. =20 Fly Safely out there =96 Ya' hear! =20 =20 Ed It is so nice of you to investigate every known failure mode, so the = rest of us lessor pilots don't have to. Thank you............ =20 The water injected, is displacing a like volume of fuel. It is not = actually the water that causes the stumble, but the fact that the engine is = starved for fuel (over lean mixture). So the cold start adds fuel and the engine runs again.=20 =20 Lynn E. Hanover =20 Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com ------=_NextPart_000_001F_01C932C6.CBEED470 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Good point, Lynn.=A0 If I had a bit better = presence of mind, I would have checked the air/Fuel ratio indicator to see if it = went lean when the engine stumbled.=A0 But, alas, I simply can’t =A0seem to = remain sufficiently detached from the situation at hand when the engine is = dying - to study secondary effects{:>)

 

Ed

 

Ed Anderson

Rv-6A N494BW Rotary = Powered

Matthews, NC

eanderson@carolina.rr.com=

http://www.andersonee.com

http://members.cox.net/rogersda/rotary/configs.htm#N494BW

http://www.dmack.net/mazda/index.html<= font size=3D2 face=3DArial>

From: = Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Lynn Hanover
Sent: Monday, October 20, = 2008 11:17 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] = Water in the fuel?

 

I always like to share happy little "incidents" with others on the list = in hopes we all might benefit – not just me {:>).  I landed = at Shady Bend none-stop from NC with the left tank empty and 14.7 gallons in the right tank. 

 

On the way returning from the Rotary Round up at Shady bend; I stopped to refuel at = WayCross, GA as I normally do.  Everything thing has been work outstandingly on = the trip thus far.

 

I took off and got up to my intended cruise of 5500 MSL (30 kt headwind there, but = bumpy as heck any lower).  With such a headwind, I knew the flight would = be uneventful (the incidents happen when I have a tail wind).    After about 30 minutes I decided to switch from my right wing tank = to my left.  So I turned on the boost pump and both high pressure pumps = and turned the fuel selector switch to the left = tank.

 

Normally there is a non-event, there is no hiccup or hesitation – = normally!   Well this time things were different, the engine started to  surge = - big time – as did my heart.  The fuel pressure is wiggling a = small amount but clearly with pressure above 35 psi it is adequate. =

 

 My mind races back to that incident a long time ago where I glided 12 miles = engine out – and I decided there was no benefit to be gained by repeating = that experience.  So as I rapidly raced cause and solution hypothesis = through my head, I reached over and turned on the cold start switch.  The = engine began to run almost normally, I switched cold start off and the surge returned.  I hit "nearest" on my Garmin and turned toward = the nearest airport (17 miles).  Then back to the engine.  It is = still surging although not quite as badly as it had been – but still way = too much to be comfortable with – and that fuel pressure is still nominally = around 40 psi.  What goes? 

 

I then turned off my secondary injectors - the engine began to run smoothly = (although I don't know if  this was more than a coincident of timing).  = So recalling my lesson learned from that earlier incident (switch tanks, = dummy!), I switched back to the right tank – happily every thing settled = down (including my heart) and the engine ran normally.

 

After getting a bit closer to the target airport, I gathered my nerves (what = remained of them) and switched back to the left tank – there was a = momentary burble, but then the engine started running normally and did so for the rest of the = flight burning 10 gallons out of that tank.

 

Naturally, I am trying to figure out what could possibility have cause this momentary hiccup.  Here is the best I can come up = with.

 

I landed at Shady bend with the left tank with approx =BE gallon in it.  It so = happens the gas cap on that tank is in need of an O ring replacement as I = noticed a small amount of fuel streaming from the cap area.  Well, the = aircraft set outside through a few light rain showers while at Shady Bend.  I = believe that water may have seeped through the cap and collected in the = tank.  (No, I did not do a drain of my tanks checking for water as I should have).  I used to do it religiously, but after 8 years of so of = never finding a single drop of water, I had lapsed in that check.  No = excuses – just the facts.

 

So if a =BD cup or water or so had gotten into that empty tank, it would naturally = have settled at the bottom – right next to the fuel pick up.  I = refueled at WayCross = putting fuel into both tanks – no problem with the right tank (with a = non-leaking cap).  So I believe that I took off with some amount of water in = the left tank.  When I switched fuel tanks that slug of water was sitting = right there waiting to be sucked into the system.  This is why (I = believe) the fuel pressure did not go down as it would have if there had been no = liquid being pumped through the system.   So it basically took a few = hair raising moments to suck all the water through the system and into the = engine – then all was well.

 

I am not certain why hitting the "cold Start" switch would have made = any difference, but I did turn it on twice and each time the engine settled down.  Also when the secondary injectors were momentarily turned = off the engine smoothed out.  It may have to do with injecting water into = the secondaries (which are positioned further away from the engine) and = perhaps the evaporative effect was sufficient to freeze the water vapor???  = Don't know, but I am convinced that water in the fuel was the most likely = cause.

 

I think the principal point is that had I done the fuel drain according to Hoyle I = would have likely discovered the water and drained it.  So once again, a = bit red-faced to admit to failing to follow long established check-list = procedures (I know none of the rest of you do that), I found an interesting = "incident" to relate to the list.

 

Fly Safely out there – Ya' = hear!

 

 

Ed<= /p>

It is so nice of you to investigate every = known failure mode, so the rest of us lessor pilots don't have = to. Thank you............

 

The water injected, is displacing a like = volume of fuel. It is not actually the water that causes the stumble, but the fact = that the engine is starved for fuel (over lean mixture). So the cold start = adds fuel and the engine runs = again. 

 

Lynn E. = Hanover

 

Ed Anderson

Rv-6A N494BW Rotary Powered

Matthews, NC

eanderson@carolina.rr.com

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