---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Wed 12/12/18: 6 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:00 AM - Yak 52TW Fuel Starvation at near zero G (ggtyler) 2. 10:23 AM - Re: Yak 52TW Fuel Starvation at near zero G (Pedro Cerveira Pinto) 3. 02:34 PM - Re: Engine calendar life HS6/M14P (jlpartington@reagan.com) 4. 04:46 PM - Re: Yak 52TW Fuel Starvation at near zero G (ggtyler) 5. 08:45 PM - Re: Re: Yak 52TW Fuel Starvation at near zero G (Walter Lannon) 6. 11:42 PM - Re: Yak 52TW Fuel Starvation at near zero G (ggtyler) ________________________________ Message 1 _____________________________________ Time: 10:00:06 AM PST US Subject: Yak-List: Yak 52TW Fuel Starvation at near zero G From: "ggtyler" Just looking for some second opinions and if anyone else has experienced this. Last week I spent 3 days doing spin and aerobatic training with Sergei Boriak in my Yak 52TW. Everything went great until the last flight of our third day. Doing a loop, just up near the top where you start to float over, the engine coughed and one or two seconds later coughed again. We were at 2100 RPM and 29 Inches. Up near the top of the loop we were just getting into a misty cloud layer. Carb heat was not on. It most definitely felt like fuel starvation. I'm familiar with mag issues, and the airplane has all new mags and wires 10 hours ago. Was a definite cough, not a misfire. Similar experiences? Any ideas? Solutions? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=486255#486255 ________________________________ Message 2 _____________________________________ Time: 10:23:38 AM PST US From: Pedro Cerveira Pinto Subject: Re: Yak-List: Yak 52TW Fuel Starvation at near zero G What was the fuel quantity in each tank? If it was less than 20 in any tank that was the problem. Cheers. Na(o) quarta, 12/12/2018, 18:08, ggtyler escreveu: > > Just looking for some second opinions and if anyone else has experienced > this. > > Last week I spent 3 days doing spin and aerobatic training with Sergei > Boriak in my Yak 52TW. Everything went great until the last flight of our > third day. Doing a loop, just up near the top where you start to float > over, the engine coughed and one or two seconds later coughed again. > > We were at 2100 RPM and 29 Inches. Up near the top of the loop we were > just getting into a misty cloud layer. Carb heat was not on. > > It most definitely felt like fuel starvation. I'm familiar with mag > issues, and the airplane has all new mags and wires 10 hours ago. Was a > definite cough, not a misfire. > > Similar experiences? Any ideas? Solutions? > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=486255#486255 > > ________________________________ Message 3 _____________________________________ Time: 02:34:57 PM PST US Subject: Yak-List: Re: Engine calendar life HS6/M14P From: jlpartington@reagan.com =0Aanyone got a stock CJ-6 engine or two? ________________________________ Message 4 _____________________________________ Time: 04:46:45 PM PST US Subject: Yak-List: Re: Yak 52TW Fuel Starvation at near zero G From: "ggtyler" My aircraft has 21 gallon primary tanks in each wing, and I had at least 13 gallons in each tank. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=486266#486266 ________________________________ Message 5 _____________________________________ Time: 08:45:29 PM PST US From: "Walter Lannon" Subject: Re: Yak-List: Re: Yak 52TW Fuel Starvation at near zero G Yes but (for a second or two) that 13 gals. was sitting on the top side of the tank while the outlet on the bottom was sucking air. Should not have been a problem since the fuel feed system (header tank or whatever) should have handled that seamlessly. You need to study and understand your fuel system. Walt -----Original Message----- From: ggtyler Sent: Wednesday, December 12, 2018 4:46 PM Subject: Yak-List: Re: Yak 52TW Fuel Starvation at near zero G My aircraft has 21 gallon primary tanks in each wing, and I had at least 13 gallons in each tank. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=486266#486266 --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 6 _____________________________________ Time: 11:42:13 PM PST US Subject: Yak-List: Re: Yak 52TW Fuel Starvation at near zero G From: "ggtyler" Walt, I'm pretty sure I have a decent handle on the fuel system. I've got a header tank under the feet, with a flop tube, and then the fuel globe on the front side of the firewall and a pressure carb. I was under the impression that this system was specifically designed to supply fuel for even a couple minutes of sustained inverted flight. Are you suggesting that fuel starvation during aerobatics could be considered normal in a Yak 52? Sergei didn't seem to think so. He's got thousands of hours in the Yak 52 and the first words out of his mouth were "that's not good". I'm trying to assess if this has been an occasional rare occurrence for other Yak owners, and what the possible solutions might be. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=486270#486270 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message yak-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Yak-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/yak-list Browse Digests http://www.matronics.com/digest/yak-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.