PT20J

THISS^^^ People make mistakes.

I've had Greg at Advanced Aircraft work on my airplane. Easy to work with and does good work. I’ve also heard good reviews of DeLynn Elrod, Reliant Aircraft Services @ 7S3 Hangar F2 503-799-9834. He repaired a sticky fuel valve on a ‘78 J for a friend.

A couple of years ago, my engine stuck a valve in Shreveport LA on my way to Sun 'n Fun. Although the FBO advertised having maintenance available, it turned out to be a part time mechanic who worked when he felt like it and didn't return phone calls. I was unable to find any other mechanic in the area. I called Don Maxwell and he sent one of his mechanics and we staked the valve and got the airplane flyable and then I flew it to Longview. Although the shop was backed up with airplanes everywhere, Don and Paul reamed my valve guide. It was Friday and they had the FBO move the plane to transient parking and loaned me their truck for the night so I could leave Saturday Morning.

https://aeromotors.azurewebsites.net/

After some thought, I doubt it makes much difference whether you keep the battery on a minder or top it off once a month. What kills the batteries is sulfation and that will come from deep discharge cycles or leaving it discharged for a long time. In normal operation, the deepest discharge comes from starting. So, the more starts, the shorter the life. Leaving it sit in a discharged condition is also bad. Float charging shouldn't do a lot of damage and it seems from reports here that people report about the same life from Concordes whether they keep them on a minder or not. These batteries are sealed and they shouldn't lose a lot of capacity unless they outgas hydrogen which only happens when a deeply discharged battery accepts a high charge rate causing an overpressure and outgassing. If a float charge was really bad, flying the airplane would be bad for the battery also. If you want the battery to last the longest possible time, don't install it and top it off once a month Otherwise, install it, don't abuse it and forget about it.

Here is Concorde’s recommendation https://batterymanagement.concordebattery.com/BatteryDocs/TB15.pdf

I just asked what the difference was between the 24V Concorde and the 24V Gill Battery Minders because I was wondering if I needed to get a different unit when I switched from the Concorde to the Gill. I don’t remember the exact details but I came away believing that it wasn’t enough of a difference to matter.

I bought my Gill in 2021 and replaced it a little over a year later when it failed a capacity check. I always kept it on a Battery Minder. I was a little peeved with Gill because part of the reason I bought it was that Gill was advertising a rebate on it's website. When I went to fill out the paperwork for the rebate, I notice that it had expired. When I called Gill they refused to honor it although the person I spoke with admitted that he forgot to remove it from the website. I've got the battery in the hangar and keep it as an emergency spare. I top it off every couple of months with the Battery Minder. Concorde's recommendation to not keep them on a maintainer continuously makes sense because any charging will release some hydrogen which will shorten then battery life. I once talked to the owner of the company that makes Battery Minders and he told me that Concorde wanted some small change in voltage. He complied but the difference was so small that he didn't really think it would matter if you used a Gill minder on a Concorde or vice versa.

Ever watch the engines on a 747 wing flying in loose formation in heavy turbulence. Now that’s scary!

Same thing here. I didn’t even call Gill. I just went back to Concorde.

Is this an experimental installation? Only one GSU 25D is approved by the STC for certified installations. If it's experimental, I believe g3xpert will evaluate the assert logs and help you get to the bottom of it.

The "probe" should just be a shunt. The shunts don't generally go bad, and if it did it would disconnect the battery from main bus. But there are two wires that run from the shunt to the engine monitor. I'd look for loose connections between the shunt and the JPI.

Bob told me that at Mooney, the number was up to the flight test engineer. They flew a number of flights and then chose a conservative number that they felt the "average" pilot wouldn't get into trouble with. One of the issues with the Mooney is that the nose gear is rigidly connected to the rudder pedals so you have to release pressure and let the rudder center when the nosewheel touches down while simultaneously increasing aileron into the wind.

I once asked Bob Kromer (Mooney factory test pilot) why the demonstrated crosswind velocity was so low and he said that the older test pilots all cautioned to be conservative because not all pilots have the same level of proficiency and most don't often practice crosswind landings. He had a personal max crosswind number that he said he was comfortable with when he was flying Mooneys nearly daily. I don't recall the exact number but it was way less than 35 knots. Somewhere in the low 20s I think.

My experience on a Lycoming IO-360 is that compare to a bayonet probe, the spark plug gasket probes read about 20 deg F high (because the spark plug is the hottest part of the head) and the piggy back probes read about 20 deg low (because they are reading surface temperature rather than the temperature in the well).

That's the 3/8" piggy back probe. It goes under the factory probe. This is the spark plug probe. https://www.jpinstruments.com/shop/cht-gasket-probe/

Is this the one you mean? It's still on the JPI website. https://www.jpinstruments.com/shop/m113-38-cht-gasket-probe/

The D rings just attach to a bracket that is screwed to the floor with an AN-3 bolt. You could just remove the bolt and ring and replace it with something else. I always liked the straps Piper used on the Cherokees. There are some for sale on eBay. You'd have to talk to your A&P and see if he agrees it's a minor alteration.

According to the service and maintenance manual, the 100 series remove from below and the 2000 series remove from the top. Service & Maint manual.pdf

The RevE Pilots Guide contains an updated description.

Bubbles, I think. There is a video on Precision Airmotive’s website.

The RSA troubleshooting manual suggests that it might be an air leak in the fuel line somewhere. 15-810_B.pdf

Does the engine run smoothly? I would think that much variation in fuel flow would create some roughness.

I created a slurry with MEK and white LEGOs, but I've also just used black ABS pipe cement from the hardware store. I put down a thin coat of cement, then press in a piece of glass cloth, then add some more cement, then more cloth and finally more cement. Usually two layers is enough unless it is an area of high stress. You don't want a big puddle of glue -- just enough to saturate the cloth. Acid brushes work well for applying the cement. I had to do some extensive repairs on my glare shield and that is the only part I had to sand down and texture. I used a SEM product called Texture Coating. You can get a variety of textures. I just sprayed it lightly which provided a light sandpaper-like texture. You can spray it on heavily and even use a putty knife to knock it down to provide other textures.

Control surface static (mass) balance can be designed in for reasons other than flutter. Balance affects control forces and stability. When done for flutter reasons, the idea is to move the surface CG at (balanced) or ahead (overbalance) of the hinge line. This causes the inertial reaction to a gust (or other pressure disturbance) to create a moment that opposes rather than reinforces the motion. The susceptibility of a control surface to flutter depends on a number of things in addition to mass balance such as structural rigidity, control surface size and shape (large surfaces and especially surfaces with wide chord are more subject to flutter than small, narrow surfaces), and control system rigidity and friction. If balance (or overbalance) is not needed for flutter prevention, then balancing can be used for stability and control force tailoring. A underbalanced elevator will increase responsiveness to initial pitch changes. However, with a constant pitch rate (as in a level 2g turn, for instance) it acts as a bobweight and will increase stick force.