All Activity

MP and RPM.

I'd definitely take a look at the data tag on the mag. The 10-79020-18 is an S6LN-25, which is an S-20 magneto, not an S-1200 mag (which is what the 420807 sensor is for). So that would definitely be the wrong sensor if that's the mag you have. If you have a pressurized S-20 series magneto, the 420806 is the proper PN per the 930 installation manual "For the pressurized Bendix -20, 200, series & S6LSC-25P and non-pressurized Slick 600 use JPI P/N 420806." There isn't enough in the picture to positively identify the mag for me, but it being unpainted, feels like an older style mag.

Owning 100% of what is the question? Let's face it the production line won't be reopened. As previously mentioned part sales are $6 million, not a lot there at the end of the day. My guess is that Meiijing has already written off their investment. They wouldn't want it back. They wouldn't want to open their checkbooks to continue to finance operations. I am not sure who LASAR is in terms of finance and deep pockets, my guess is they thought this was an opportunity to add marginal revenue without a lot of work, I suspect they are wrong as somebody who has bought a company that needs work. Never again. Probably the reason Don Maxwell passed, that would have made more sense. Just internet speculating.

I'm going to check again on the mag. I don't see them being replaced in the logs with a pressurized version, and my engine is a GB from 79 so I don't think it was changed over to pressurized mags. But that sure does look like a hose going into the mag now that you point it out And that sensor looks a lot what my wire and I saw something on the mag that looked like I imagine that does under the shrink tube. Maybe it just pulled out? I'd expect that to be crimped in I guess.

I suspect I'm going to find something very rigged, considering the whole thing I'm holding is a set of butt splices. I looked in my logs and the mag is 10-79020-18, the unpressurized mag it looks like. I suspect the wiring is all the same it's just sensor end that's different. I suspect that for whatever reason when they where installing the EDM they ordered the wrong sensor, then cut off the end and wired it up to an existing sensor from whatever was in there before I guess. I need to get back to the plane for a better look to be sure, I didn't know what I was looking for yesterday when I had it apart. I suspect I'll find something loose from the sensor, might just end up ordering a new one to clean this up instead of adding yet another butt splice.

You are correct that many high tolerance structural parts and most brackets are predrilled. But I don't think skins are predrilled. Here is a NOS Mooney factory wing skin for sale. Mooney RH Wing Skin P/N 220000-194 NOS (1022-669) – Safe Skies Aviation, LLC

That picture sure looks like a pressurized mag to me? Isn't that a hose going in to the mag right there? So the 420807 sensor mounts underneath the calibrated leak orifice plug on the magneto. Most of the pictures that you'll see online linked to the 420807 are the wrong picture... It's more like a washer with a lead. I'll attach a picture below. It would likely be a pain to pull the orifice and change the sensor with the mag in place, though depending on the clocking of the mag, it might be possible.

Actually there are bigger problems: It appears that the 180 HP Austro 330 weighs about the same as the Rocket 305 HP TSIO-520 Installing the Austro in a M20E actually derates it at sea level from the original 200 HP Lycoming As you point out batteries and more lead will be needed in the tail to keep the M20E off its nose with the additional 250-300 lbs on the nose. UL will drop to about 500 lbs...maybe less Maybe a fairer comparison would be the Continental CD-300 used in the Diamond DA-50RG. It has a dry weight of 560 lbs...probably closer to 600 lbs installed.

Just to be clear if it is not already, the multiplier (13.7 or 14.9) only applies to LOP ops. The formula does not apply if the engine is operating Rich of Peak. When LOP the power output is determined solely by fuel flow, or so the GAMI people tell us. While ROP it is determined by both MP and FF. Have to go to the POH tables for ROP ops power. I have a JPI 930. I have well over a thousand hours flying with it. I ignore the % power display, it is based on an algorithm and the algorithm needs a calibration factor called the "K factor." The K factor is supposedly pre-set from the factory for your aircraft. From many hours of experience with the 930 the display is just not accurate. It is about 7 - 8% off in my aircraft. And how would you as the pilot calibrate the K factor? With what instrumentation? You would need instrumentation that would accurately read out the BHP the engine is producing while in flight. The one way I found to approximately calibrate it is to learn to operate LOP, then make a LOP power setting while flying the aircraft in level flight. The LOP formula can then be used to determine percent HP and note the airspeed. Then get out of LOP operations and, while still in level flight, operate the engine ROP, allow the airspeed to stabilize (t takes a little bit in a Mooney) and determine what ROP combination of MP and FF is required to produce that airspeed. Then look at the percent HP display and note how far off it is from the percent power you obtained using the LOP formula while in LOP operations. Adjust the K factor so the percent HP display is correct for that ROP power setting. I never did this in my own aircraft, it seemed like alot of screwing around to get the display to read approximately correctly. I just ignore the % power display, it is not required equipment.

TSIO-360-GB. Local mechanic says "they are rare but we can get them in, I won't do the inspection as I've never seen one pass we only replace them". My normal mechanic says he's had it on backorder for me for over a year and has signed off two annuals with it. I'm due again soon for the recurring, and I want to do my own due diligence on the part lookup. My logs indicate the part number should be 646534 (when it was last replaced). Continental doesn't show any superseded part numbers so that means it's the right part? They list Boeing as the supplier (with no supply of course). Spruce has it as "special order". I know these things are apparently completely unobtanium, but I want to make sure of that before I firmly tell the local mechanic to go pound sand. I'd also like to get my hands on one before it inevitably fails an inspection.

Here's the page for the JPI sensors. https://www.jpinstruments.com/shop/rpm-sensor-for-bendix-mag/ I would confirm what mag you have and then call JPI to confirm the correct rpm sensor part number. If you don't have the correct part, I'd get the correct one. If your part is correct, I'd just splice the wiring either by re-pinning the Molex connector if there is enough cable or using butt splices if not.

Just the JPI.

Glad you got the motor stuff sorted out. Do you still have a mechanical tach, too, or just the JPI?

The battery management systems on most modern battery packs will already limit charge to 80%, or whatever their determined limit is, and manage the battery cycles. When they show 100% (all lights, or whatever), they may really be at 80% to self-limit life management. We use some industrial ruggedized tablets that do that, but they really only show 80% when charging and just stop there, so they never show 100% except in some unique charging conditions. IIRC the battery in the Mooney that burned had been dropped on the pavement just before the flight. If something like that happens, be very careful with the battery. I use a pack that powers my Stratux ADS-B receiver. I plug the Stratux into the battery and the battery into a USB charge port adapter in the back seat. This keeps the Stratux on even between temporary ramp shutdowns, etc. Seems to work well that way and I've never had any trouble with it.

I don't think that was mentioned in this thread:

On descent in my C, I push for 500 fpm and trim it hands off. As I come down, MP and EGT both increase, so I pull the throttle back to my former cruise setting and push the mixture forward to about my former cruise EGT. When leveling off, I reduce throttle, then RPM, to match my desired power setting (or airspeed for pattern entry) and lean again.

WOW! I had forgotten about that. Just curious, do you remember what kind of battery pack? Was it a major brand or just something you picked up online or in some store? ADDED NOTE FOR ALL... It goes against traditional logic since you're dealing with a stored power cell. But current best practice is to dump WATER on the battery. Even better if it is in a fireproof bag and you can fill the bag with water.

Good point about CHT. Also on the list of "look for the obvious" first - with new jugs, the fuel injectors were removed from the old jugs and reinstalled on the new. Something as simple as dislodged debris could be reducing fuel to #4 causing it to run lean and hot. And - are you sure that they got the injectors installed on the correct cylinders? Shops do make mistakes...perhaps more nowadays.

Here’s some more simplification from a fellow Air Force guy. Break your “leaning plan” into a few chunks since they have different goals: Takeoff and climb - full rich, full throttle, full rpm. Use airspeed higher than Vy to keep CHT temps in limit, maybe ~115mph climb. As you climb above ~3-5000’msl, you can slowly start to lean using target egt as long as temps are in control, however you can also keep it full rich. Prop stays full rpm, and full throttle. Cruise - you likely just need to use rich of peak or peak as you might have trouble getting lean of peak in a C. You will want to use a key number for 75% power or less (for engine longevity) if youre below about 7000’. Above that, wide open throttle is below 75% anyway. Rpm probably 2500 or 2400, whatever feels smoother. Less rpm equals less power though. Lean to 100 rich of peak is good - do you know how to do this? If you’re sure you’ll be 65% or less, maybe try peak egt which basically coincides with lean to rough and then add a little until it’s smooth. Descending - maybe leave cruise power and enjoy the extra speed. You might need to slowly get richer as you descend until you are in the pattern and then you probably want full rich, full rpm to be ready for a go around.

I agree and do not carry a battery pack any more in a small airplane, especially since this Mooney burned up after a battery pack caught on fire after being dropped. Thank goodness it happened on the ground and not in the air. https://asn.flightsafety.org/wikibase/386971

You specify EGT but did not comment on CHT. CHT values are absolute, where EGT is really about relative values, such as degrees from peak or watching a trend on a given cylinder. There are things about EGT that can lead to variation between cylinders that is not meaningful. Simply where the probes were drilled and inserted will give big variation. In this case, assuming they used the same holes, the tip may not penetrate quite the same distance, tip is bent a little, or the flow from this new cylinder is slightly biased in one direction versus the previous one as it flows during exhaust valve opening.

Don's modification was most likely just entering the header parameters for his engine. A search on the file name pointed me to egtrends.com, a site that no longer works. As I recall, I looked there when I originally downloaded the file about 9 years ago (the version I posted in this thread is in the the file section on Mooneyspace, I think), and was able to get into the thermo formulas used to build the spreadsheet. I was satisfied with their veracity at that point, although I can't remember if there were any coefficients used to adjust the theoretical to the empirical. Might have been, based on the accuracy of the output.

I can see @hazek's safety concern. It would be a pretty different situation in a Mooney vs being a Pax in a commercial airliner. You can't exactly jump up out of your seat and stand in the isle as you get the fireproof bag. And granted, the major manufacturers (UL Approved) batteries are much less likely to have a catastrophic runaway issues. But it still can happen. I have a battery pack, but then I try to charge it, my flashlights, etc., to 80ish percent. I don't have a real way of knowing, but my battery pack does have lights to show how charged it is, so I stop at 4 out of the 5 lights. That last 20% is the hardest on the current type of batteries.

Unlike the Rocket, there is no legal amount of lead or batteries in the tail that will fix those numbers.

Love those numbers! Were they 520s like Erik?