PT20J

I like my Aspen, though I've only got one tube. Do you fly instruments using it with synthetic vision? I find the pitch axis and horizon line a little indistinct for flying precisely with SV on and don't use it on approaches. Wonder if the MAX is better? Skip

I'm a "boomer" and I've been declined.

Good points, Paul. I agree that setting up two nav systems should not be overly challenging since I can do this at a low workload time. My thought is that the workload to monitor two navigation systems during a non-precision approach with no vertical guidance (I won't get LNAV+V on this) while descending close to the ground may be more workload than I might want. This is a nit perhaps, but I don't believe using the HSI bearing pointer on the VOR (it would be OK for an NDB) is what the FAA had in mind when it stated that the underlying NAVAID must be "monitored for final segment course alignment." You really need a second CDI to do that with accuracy. So now I am modifying my scan, trying to correlate two CDI indications (with the VOR perhaps scalloping a bit) while descending close to the ground. It absolutely can be done. And, if I had an operational need to do it, I would. I just think it's not the best situation. Skip

Perhaps I misunderstood the OP's question as wanting to know if GPS could be used in lieu of the VOR or NDB. There's a nuance here. While Paul correctly points out that paragraph 5 allows the use of GPS to navigate a final approach segment if the the NAVAID is operational and you monitor it for the final course alignment, the preceding paragraph 4 states that "Pilots may not substitute for the NAVAID (for example, a VOR or NDB) providing lateral guidance for the final approach segment." So to do this correctly, you have to set up and monitor two navigation systems during the final approach. That's a lot of workload and if I really needed to do it for some reason I'd have the autopilot flying the GPS and me monitoring the VOR (or NDB).

From another post... The SureFly (missing) advance curve has been bugging me, so I spoke with Jason Hutchison at SureFly. He confirmed that they removed it from the website. He said it was an oversimplification and technically incorrect. He also said that they decided for reasons he declined to elaborate on not to publish the corrected curve(s). He was pretty forthright and I didn't get the sense they are trying to hide anything. I suspect that they are tired of "experts" opining on the details of their design. OK, I get that -- I probably wouldn't get too far trying to get Subaru to send me advance curves for my Outback. Here is what I did learn: The primary design goal of the advance is to adjust timing so that the peak pressure point (PPP) is about 13 degrees ATDC which they found to be close to the Maximum Brake Torque (MBT) angle for most engines in cruise operation. Operating at MBT gives the greatest efficiency. The use of MAP and rpm is analogous to the old auto distributors that had centrifugal and vacuum advances. At 24" MAP and above, the SureFly will be at base timing. Below 21" it will be fully advanced.

Yes. As to stumbling when hot, one possibility is that there is an induction leak that gets worse as things heat up and expand. Gaskets where heads mate with risers seem to be problematic as well as the seals where risers mate with sump if not installed correctly.

That's because the rapid acceleration causes the prop to momentarily exceed the speed that it can maintain with the engine at full power.

Not at low airspeed.

To make rated static rpm requires near rated power. That's how the setting for the low pitch stops is determined. The governor doesn't come into play until you have significant airspeed. It's why you check rpm early in the takeoff roll -- it's not a check on the governor, it's a check that the engine is putting out the proper power. Similar to the field barometric check on radials.

You are not allowed to "make up" an approach with GPS -- you have to use the ones loaded in the database. The FAA won't allow a database to include an approach that the GPS is not approved to use. So, as far as the GPS is concerned, if it's in the database, you use it; if it's not, you can't. Skip

I think Formula 409 also says not to use on aluminum -- at least is used to.

That's what I do. It can even improve your credit score since the more credit you have approved -- and don't use -- the better your score (up to a point).

If you haven’t removed the baffles from the old engine, they will still be there. It’s easy to overlook them and send them back with the core, or have them fall out and get lost when you remove the baffles. They are $35.60 each from Aircraft Spruce.

Thanks for letting us know the outcome.

They quoted me two full days to do a prepurchase inspection. Plane was sold before I got that far and I bought one in Texas. Don Maxwell did a thorough inspection in about 6 hours. I’ve heard good things about Troutdale OR MSC. Skip

I’m going to have to do this this winter. Anyone tried 3M General Purpose Adhesive Remover? Skip

You are allowed a maximum dent of 1/32”. If it needs to be replaced, I’d see if I could retrofit the newer design with stops. Skip

The reason to torque a bolt is to stretch it a predetermined amount which gives it optimum fastening capacity. The proper way to torque a bolt is to torque the nut if at all possible. Torquing the bolt can result in low torque due to added friction and also wears the cad plating off the shank. Nonetheless, occasionally it’s the only way to do it. For self locking nuts, you are supposed to measure the run up torque and add that to the torque value.

Only a few bolts -- usually in engines -- are one-time use. General purpose hardware can be reused unless it's been over torqued and stretched or otherwise damaged. Lock nuts can be reused unless they run up finger tight. But, hardware is cheap and if you don't know the history of a fastener it's probably best to use new. Years ago during a factory tour someone told me that Al Mooney had calculated that he could use a size smaller on the upper engine mount bolts but thought it didn't look right. Here's the info on the nuts for for the baffles from the Lycoming IPC. BTW it's best to check all the mounting details with the IPC and Maintenance Manual. Don't just put it back the way you found it without checking because the last person may have done it incorrectly, which is not uncommon on Mooneys I've learned. Skip

If you are changing from an A3B6D to an A3B6 don’t forget to put the strap on the ignition switch to ground out the right mag during start. Skip

You can also make a funnel from a plastic Coke bottle. The threads mate with the Lycoming dipstick tube. Screw one on and cut the bottom off at the appropriate angle with a box cutter.

Might be true for a C or D as indicated in the reference. The J service manual is different. As I said, we had no problem R&R ing the engine without removing the engine mount from the airframe. Skip

I don’t think you can mount the pedals without the brakes — they will flop down since the brake linkage adjusts the pedal angle. I’d make some wood blocks and mount them temporarily for practice. Then you haven’t really permanently modified the airplane.

Scary. Glad it worked out OK.

The engine comes bolted down to a pallet covered with wood frame and heavy cardboard and a foam "donut" on top of the engine inside the carton for cushioning. Unless the carton is seriously damaged, everything inside will be OK. The tip 'n tell is a little arrow with plastic beads that can only flow one way and indicate if the carton has been upended. Open carefully as you will need the carton to return the core. We had the driver wait until we opened the carton and made sure it was good and then we signed for it. Unbolt the engine from the pallet and lift out with an engine hoist. Put the old and new engines side by side and transfer parts you are reusing from the old to the new. Commonly missed are the fitting for the oil pressure sender and the sniffle valve. Install all the components on the accessory case -- it's much easier now than with the engine installed. And don't lose the barrel nuts used to bolt the baffles to the cylinders -- they are special Lycoming parts (Spruce stocks them) and cost $35.60 each. (I spent an hour looking for one that fell out of the cylinder and rolled across the shop floor into oblivion). Baffles can be attached with the engine installed. When you remove the old engine mounts, note the position of the shims so you can reassemble with them in the same position. Use new LORD mounts. Some install the engine mount to the engine and then the whole assy to the firewall. We didn't do this as the engine mount was in good condition and we never removed it or the wiring attached to it. We had no trouble attaching the engine to the mount on a 1994 M20J. Skip