Bob - S50

You'll end up finding a typical fuel flow that is LOP for the power settings you use. For me that's usually about 9 - 9.4 GPH. So if I'm going to use the lean find feature, I'll pull the mixture back to about 10.5 GPH and start from there. You can also use the LF feature starting from the LOP side which is what some people advocate. To do that, I'd pull the mixture to about 8.5 GPH and then press the button. I'd then enrichen until I saw the first (not the last) cylinder switch over. That's because it's actually showing I've gone ROP on that cylinder while all the others are still LOP. I'd then start leaning again and watch that cylinder go back fewer and fewer degrees below peak. At some point continuing to lean would start to increase the number of degrees below peak. I'm now LOP on that cylinder again and I'm done leaning. To say that another way to hope to reduce confusion, on my engine I might see the #1 cylinder go from 0 to -10 to -15 while I'm enriching. I'd then lean the mixture and watch it go from -15 to -8 to -2 to -5 to -8 while leaning. I've now gone from ROP to LOP.

If you want to be able to quickly lean without spending a bunch of time looking at the engine monitor, here are a couple ways to do that: First, spend some time leaning while using the engine monitor at some of your favorite power settings. For me that's 2600 RPM and 22" when below about 6500'. If I'm going higher than that I'm probably going a long way and I'll be up at 8500' or 9500' in which case I'll be 2600 RPM and WOT. I cruise LOP at all those settings. For each of those favorite power settings, find out what fuel flow you get. Do that several times to ensure you are getting consistent numbers. For me, down low it's about 9.2 to 9.4 GPH. Up higher it's somewhere between 8.7 to 9.2 GPH. Once you know what the fuel flow is you can use that knowledge for future flights. Level off, set the RPM and MP, then pull the mixture to the desired FF. Second way would be to pull the mixture until you feel a loss of power (not necessarily roughness), then increase the mixture until you feel the power come back. Personally, if I'm doing a step climb and I'm only going to be level for a few minutes, I'll lean by watching my #1 EGT until it peaks because that is almost always my richest cylinder. If I'm leveling at my cruise altitude, I'll use the lean find function on my engine monitor.

Nice looking plane.

In the DC9 we called speedbrakes erasers because you only used them to correct a mistake.

Just a little bored sitting around the house so I thought I'd post this link: Where I live and fly. The top live camera is at KPLU. I live about 2 miles on the other side of those trees. The bottom live camera is S50 which is where we base our plane. If you had been watching yesterday you would have seen me a couple times on both cameras. Stay healthy.

I'm just up the road at S50.

You need to download the current version of the pilot guide. The version I have tells you how to load a hold at a waypoint on page 4-14.

Remember, if the course really was off by 6 degrees, at 15 DME, you would be about 1.5 miles away from where ATC was expecting you. That is not insignificant. The larger the DME, the greater the error.

WARNING - long answer from an engineer. This is your basic engineering statics class. Anything forward of the datum point is a negative arm. If we view the aircraft from the left side, negative arms and the prop will be left of the datum point. Any weight added in that area will be a positive weight times a negative arm which will result in a negative value indicating a counter-clockwise rotation relative to the datum point. Any weight added to the right of the datum will be a positive weight times a positive arm which results in a positive value. That indicates a clockwise rotation relative to the datum point. If you remove weight, it's a negative weight so you get the opposite results. CG is calculated by dividing the total moment by the weight. If you put a fulcrum under the CG the airplane will balance. It's pretty intuitive that removing the prop will move the CG aft. Removing a weight from the front of the aircraft will provide a positive moment. Even though the weight has decreased, the moment has increased. That's because the CG has moved aft. So even though the total weight is less, the arm is longer resulting in a larger moment. Either reducing weight without changing the moment or increasing the moment without changing the weight will move the CG (moment/wt) aft because either a larger top value or a smaller bottom value will result in a larger value for CG. So for example, if you removed the prop and put it in the cabin, the weight would be the same but the moment would increase and the CG moves aft. Likewise, if you were able to remove weight that was directly over the datum point (vacuum pump?) the moment would not change but the weight would decrease so the CG would again move aft. If the moment decreased when you removed the prop (which it doesn't), one change would offset the other and the CG would not move much. Interestingly, you can pick ANY datum point you want, measure arms and weights, multiply to get moments, and divide by total weight. While the distance to the CG from the datum point would change, the actual location of the CG of the airplane would calculate out to be in the same physical location. So they could have picked a datum point of the prop and had nothing but positive values. But the CG range would be more like 75 to 81 inches instead of 45 to 51 inches.

I don't know. That's the POH that LASAR gave us when we bought the plane from them in 2013. The cover says it is for serial numbers 24-0378 to 24-0763. Ours is 24-0576.

Great video. Thanks. One comment about the IFD. It appears to have the same issue the GTN would have if we used the GTN to manually create a waypoint (holding fix) using radial and DME. You'll notice that the route you were on was a 308 degree course. But when you created the fix as the LIB 128/15, the inbound course to the holding fix became 302 degrees and the course from that fix to LIB became the 314 course. There is now a kink in the road. You are not really holding on the current course. To truly hold on the current course you would have to go back and modify the holding fix. Since it was off by 6 degrees, I would probably try making the fix the LIB 122/15 and see if the inbound and outbound courses became the same. The problem is caused by the fact that the GPS does not know the actual magnetic variation. Instead it uses an algorithm to calculate an estimated magnetic variation for its current position which can be off by several degrees. That's not usually a problem when navigating fix to fix because it's doing the calculations using true headings and then converts to an approximate magnetic heading for our benefit. But when creating a fix starting with magnetic, the difference between actual and assumed variation becomes significant. That's the same problem we run into when we are cleared by ATC to a radial/DME to intercept an airway and we use the GPS to create a user waypoint for that fix. It most likely is not really at the correct point. That's one case where I would use my trusty old KNS80 to create the intercept point and navigate to the airway before using the GPS to navigate.

Yep, I can read.

Our html file that calculates W&B automatically adds in 6 quarts of oil which is the level to which we fill the engine.

The POH for our '78 Mooney, step 3 of weighing says to drain the oil.

Glad we are in the minority. We drained the fuel and oil and leveled the plane with blocks on the scales before we took our measurements. Nice to know we have a UL of 1013 pounds that way.

Well... Unless I'm mistaken, you still have a couple mistakes in there. First, some general information. If you remove a weight, that's a negative just like it shows. Since the prop is forward of the reference point that makes the arm a negative too. Negative times negative is positive so the moment arm increases. When you add the new prop the moment will decrease. Here are my calculations: Weight / Arm / Moment 1747.10 / 46.84 / 81834.16 Starting point -53.75 / -30.16 / +1621.10 Remove prop 1693.35 / / 83455.26 Result -3.6 / -29.18 / +105.05 Remove spinner 1689.75 / 49.45 / 83560.31 CG calculated by dividing moment by weight +58.10 / -30.16 / -1752.3 Add new prop 1747.85 / /81808.01 Result +3.10 / -30.16 / -93.50 Add spinner 1750.95 / 46.669 / 81714.51 CG calculated And as a way to verify that is correct, your moment should not increase (CG moving aft) when you are adding weight forward of the reference point. However, I think you have another mistake. When you removed the old prop and spinner, the arm was different for the prop than the spinner. When you added the new spinner you used the same arm as the prop. If you MEANT to use -29.18 for the spinner arm, the moment would be -90.46 instead of -93.50 with your final calculations of: 1750.95 / 46.67 / 81717.55

When I plant one I usually say "take that runway!"

Apparently not.

I had an occasion to fly at 9500' yesterday to compare speed pre-yaw damper vs post-yaw damper. Pre-yaw damper, cruising just barely LOP at 9500' I would see 157 KTAS. If I remember right, fuel flow was about 9.0 to 9.3 GPH. That speed was calculated using our TAS indicator by aligning the OAT with altitude and reading the value. Yesterday I did the same thing. Fuel flow yesterday was 9.1 GPH. Using the airspeed indicator I got 160 KTAS. Using the TAS calculator utility on the GTN650 I got 161 KTAS. So it appears that the yaw damper is about a 3 - 4 knot speed mod.

And if they haven't even submitted it to the FAA for approval yet then we have another year or two to wait.

Replace with a SureFly?

I always seem to run contrary to the mainstream. While GPS can be substituted for DME, that sometimes requires mental math. And if the GPS system ever goes down (unlikely) you won't have that either. If you want DME you might consider a KNS80 VOR/LOC/GS/DME in one box that can be had pretty cheaply these days. I just bought a used one for $250 to keep as a backup for the one currently installed in our panel. That guy had a second one for sale. Between the GNS430 and GPS175, both have advantages. The GPS175 will be supported longer and will allow easier loading of flightplans. But the GNS430 has a Comm radio which the GPS175 does not. The GNS430 would allow you to get rid of one of your nav/comms. You might also consider the GNX375 instead of the GPS175 since that would allow you to get rid of your transponder and give you ADS-B OUT and IN. People are starting to sell GTN650's too because they feel compelled to have the latest and greatest GTN650Xi. That would give you the GPS, Comm, VOR, LOC, GS and allow getting rid of a Nav/Comm What you end up with depends on how many Navs and how many Comms you want, how much panel space you have, and how much you are willing to spend. Good luck.

I didn't know any of my partners until we got together to buy the plane. We ironed out the agreement first, then found the plane. I have no complaints. The only difference is that I bring a wet wash mitt with me every flight and remove the bugs and bird crap when I'm done flying for the day. The others are not as faithful. However, they have occasionally crawled under the plane to clean the belly which I've only done during the annual when the belly was not under the plane. We always fix things when they break and our partnership is structured to allow some partners to pay more for upgrades than others in exchange for a larger percentage share of the LLC.

Agreed. The best a TT user could do would be to set a track, wait until established, note the heading, and adjust the track to get the desired heading.

But of course the most important piece of safety equipment sits in the left seat.