---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Fri 12/19/03: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:40 AM - Re: Waycross, GA formation clinic (cjpilot710@aol.com) 2. 05:49 AM - Re: Waycross, GA formation clinic (cjpilot710@aol.com) 3. 06:03 AM - Re: Re: Yak-List Digest: 22 Msgs - 12/17/03 (Brian Lloyd) 4. 11:25 AM - 52TW (Jerry Painter) 5. 03:21 PM - Re: What did you do today (YakL1@aol.com) 6. 07:10 PM - Gear fails to retract. (egon) 7. 07:36 PM - Re: Booster Coil (Walt Lannon) 8. 08:14 PM - Re: Gear fails to retract. (cjpilot710@aol.com) 9. 09:36 PM - Fuel feed (Walt Lannon) 10. 10:29 PM - Re: Gear fails to retract (egon) ________________________________ Message 1 _____________________________________ Time: 05:40:49 AM PST US From: cjpilot710@aol.com Subject: Re: Yak-List: Waycross, GA formation clinic --> Yak-List message posted by: cjpilot710@aol.com Thanks. Walt. You'll be missed. ________________________________ Message 2 _____________________________________ Time: 05:49:24 AM PST US From: cjpilot710@aol.com Subject: Re: Yak-List: Waycross, GA formation clinic --> Yak-List message posted by: cjpilot710@aol.com Troops, We have a checkpilot for the clinic at Waycross. Mike Filucci will be showing up on 17th and 18th. I contacted the FBO yesterday and they are ordering up more oil. Make sure you check with the DaysInn people. We have a cut rate there. The FBO is letting us use 10 passenger van but there rental cars available there, plus one of our members is driving in. Still have room for a couple more FNGs. Jim Goolsby 302 764-4509 until the 2nd January ________________________________ Message 3 _____________________________________ Time: 06:03:34 AM PST US From: Brian Lloyd Subject: Re: Yak-List: RE: Yak-List Digest: 22 Msgs - 12/17/03 --> Yak-List message posted by: Brian Lloyd Jerry Painter wrote: > --> Yak-List message posted by: "Jerry Painter" > > I suppose almost of us have flown Cessnas with a "both" fuel selector and > have noted that the fuel doesn't feed evenly from the tanks on them, either. There is an interesting technical paper on the problems Cessna has had with the "both" system feeding fuel evenly. Cessna redesigned the system three or four times to try to fix the problem and was never completely successful. One of their problems was that one tank remained full because fuel would siphon from one tank to the other through the vent line. If you can lay hands on this paper it will give you a lot of food for thought when thinking about whether or not you want to muck about with your vent system. I haven't seen any sign of the siphon problem with the CJ6A vent system except when the tanks are completely full on the ground and the fuel expands on a warm day. > My experience with CJ's and -52's is the same as with Cessnas: Keep the > ball in the center and the fuel feeds evenly. Easy to say, hard to do. I agree with this 100%. Having the wings even the tiniest bit out of level will start an uneven fuel feed. -- Brian Lloyd 6501 Red Hook Plaza, Suite 201 brian@lloyd.com St. Thomas, VI 00802 +1.340.998.9447 - voice +1.360.838.9669 - fax GMT-4 ________________________________ Message 4 _____________________________________ Time: 11:25:08 AM PST US From: "Jerry Painter" Subject: Yak-List: 52TW --> Yak-List message posted by: "Jerry Painter" Steve, I'm glad you finally got the problems with your TW fixed. I guess if you don't mind buying a new airplane and then letting the factory/dealer keep it to use it as a test bed for a couple of years to fix all of the problems the factory should have taken care of before releasing the airplane, a TW is the way to go. Maybe all new airplanes should have a couple hundred hours on them when you take delivery two years after the date you were promised. Maybe the FAA isn't so bad, after all. I recall some very threatening comments by you because of all the problems you were having. I am no longer representing Aerostar because of all the problems I had with them, their airplanes, and their worthless warranty. Did they give you a new engine or did Gesoco have to buy it? They shipped a "new" TW to me with a bent master rod and then blamed me for it and wouldn't cover it under warranty. It also had twenty-year-old cylinders on it, a sheared vacuum pump drive, an air compressor that failed in less than 20 hours, a prop governor that didn't work properly, worthless fuel gages, a ridiculous fuel system with tanks with built-in flow blockage and improper venting that relied on leakage through the pumps and then siphoned between tanks so you never knew if you could fly aerobatics in cg, a radio that didn't work, hopelessly distorted canopy frame that wouldn't even close, an agricultural tailwheel attachment that was ready to fall off, etc etc etc. Unfortunately, your experience and mine was apparently typical. Maybe they've improved. Hope so. I'm amazed Gesoco has stuck with them--of course he has a significant investment in the design. Good luck, Mark(s) and Bill. As I recall your problems were even worse. If your cowling is easy to remove/install and works well it must be significantly different than what the airplane was originally shipped with--the stronger linkage you mention etc. As you know, the -52/W and original TW cowling/flap arrangement is so leaky around the rear and bottom that the seal was necessary to get air to even go through the exit flaps. As I recall, your cowling was particularly ineffective and had to be significantly modified in the area of the exit flaps to get it to work at all. Removing or replacing the lower cowling is greatly hampered now that everything is all sealed up because you can't get your hands in to access the attachment pins. Maybe yours is different now--I hope so. I was a big booster of the TW, love -52's (except for their speed) and was the western US representative for Aerostar for a couple of years because I believed they had a potentially great product at a great price. I still believe the potential is there--maybe they've climbed the hump--but I had nothing but trouble from beginning to end with Aerostar and their products. Not an experience I'd care to repeat or pass on to others. And I don't think it's right to subject your customers to endless waiting, then get an unproven product with no warranty. I'd much rather have an old Communist model, unmodified -52. -52's may be great fun for aerobatics, powerful etc., but they are ridiculously slow for the power. Enclosed gear and 400hp should have made the airplane at least as fast as a Cherokee with half the power. Hell, I've got a Cessna 140 that's almost as fast on 1/4 the power. And I still wouldn't flat spin one, especially if I couldn't tell where the cg was because of uncommanded fuel transfer. Caveat emptor. Having said all that, with a proper cowling CJ's and -52's would probably be significantly faster. Remember what Lopresti was able to accomplish with Grummans and Mooneys with relatively minor mods. For starters, close the cowling bottom and install a Rare Bear spinner and outlet flaps that seal to fuselage fairings anyone? Jerry Painter Wild Blue Aviation ________________________________ Message 5 _____________________________________ Time: 03:21:17 PM PST US From: YakL1@aol.com Subject: Re: Yak-List: What did you do today --> Yak-List message posted by: YakL1@aol.com Cool, Dennis. John ________________________________ Message 6 _____________________________________ Time: 07:10:35 PM PST US From: "egon" Subject: Yak-List: Gear fails to retract. --> Yak-List message posted by: "egon" Gday all, Got a bit of a problem that I could use some advice on. Recently I bled the air out of the Emergency system of my CJ. On the next flight as I suspected it might, the gear did not retract. After use of the non-normal checklist, gear retracted normally. On subsequent flights, the same thing happens. I thought that maybe the Emergency air valve might be leaking, but the EMG system seems to be holding pressure just fine.It seems like the EMG extension valves are not seating correctly in the normal mode of operation. Is there a maintenance proceedure that I am not aware of for resetting the system? If any one has any ideas, I sure could use them! Thanks in advance. Regards Egon. ________________________________ Message 7 _____________________________________ Time: 07:36:16 PM PST US From: "Walt Lannon" Subject: Re: Yak-List: Booster Coil --> Yak-List message posted by: "Walt Lannon" Hi Jim; Don't know the answer directly. The point gap setting is not given in the Chinese manual or , for that matter in the Harvard 2 or T6 manuals. However, I do have a 1939 Bendix/Eclipse manual that describes the process of repair and re-adjustment of the contact points. The Chinese/Russian unit is a direct copy of the Eclipse. If you will send your FAX no. off the list I will get it to you. Best of the season; Walt ----- Original Message ----- From: "Jim Griffin" Subject: Yak-List: Booster Coil > --> Yak-List message posted by: "Jim Griffin" > > Anyone know what the point gap setting is on the booster coil in a CJ6? > Jim Griffin > > ________________________________ Message 8 _____________________________________ Time: 08:14:54 PM PST US From: cjpilot710@aol.com Subject: Re: Yak-List: Gear fails to retract. --> Yak-List message posted by: cjpilot710@aol.com In a message dated 12/19/2003 10:11:13 PM Eastern Standard Time, egon@hinet.net.au writes: > Gday all, > Got a bit of a problem that I could use some advice on. Recently I bled the > air out of the Emergency system of my CJ. On the next flight as I suspected > it might, the gear did not retract. After use of the non-normal checklist, > gear retracted normally. On subsequent flights, the same thing happens. I > thought that maybe the Emergency air valve might be leaking, but the EMG system > seems to be holding pressure just fine.It seems like the EMG extension valves > are not seating correctly in the normal mode of operation. Is there a > maintenance proceedure that I am not aware of for resetting the system? If any one > has any ideas, I sure could use them! Thanks in advance. > > Regards Egon. > Egon, One of your emergency shuttle valves is not seating properly. There are three of them. One on each main gear actuator and the nose gear one is located on the fire wall just above the front rudder bar. Take them apart, clean and lubricate them, than reinstall. They are very simple but can hang up "open" and it does not take very much at all. Becareful when you loosen the lines to them. Sometimes the flow reducers are located in these same lines and may fall out unseen. JIm ________________________________ Message 9 _____________________________________ Time: 09:36:12 PM PST US From: "Walt Lannon" Subject: Yak-List: Fuel feed --> Yak-List message posted by: "Walt Lannon" I agree with Jerry and Brian's comments on this subject which, in summary, is if all components i.e.: vent lines, flapper valves and fuel lines are in good order the system should feed fairly evenly, though an out of trim situation will have an effect. But, are all these things in good order? One item has bothered me since I first looked at the Chinese flapper valve. That is the amount of closed surface area of the valve. There is a phenomenon that I'm sure most of you are aware of (I will call it surface tension though I know that is incorrect but can't remember the proper term - help me out Brian) that when two perfectly ground and lapped surfaces are placed together so that all air is excluded the surfaces are held together by atmospheric pressure: 14.6 psi. The valve surfaces dry do not meet that standard, but how about wet? Assuming that was possible (as some rudimentary tests indicated) and based on the measured closed surface area and an estimate of the actual opening fuel pressure from the tank it could take an imbalance of a full tank to overcome that force. As a result I have modified a set of flapper valves to near line contact, a reduction of about 90% in surface area and will be installing them for testing shortly. A second item is the difference in length of the main tank vent lines. The right one is significantly longer than the left and of course of the same diameter. I don't know enough about fluid dynamics to determine if this has enough effect on vent airflow to make a difference. It would have with more viscous fluids. An option would be to install a larger dia. vent to the right tank but this may be a complete waste of time and effort. What are your thoughts? Cheers; Walt ________________________________ Message 10 ____________________________________ Time: 10:29:00 PM PST US From: "egon" Subject: Yak-List: Re: Gear fails to retract --> Yak-List message posted by: "egon" Hi Jim, Thanks for the reply. I thought that might be the problem as well, but if one of the shuttle valves was sticking, would'nt that only affect its own particular gear leg? Is it likely that all three are sticking??? Cheers Egon.