C-182Q N96934 at West Valley Flying Club

Wednesday, January 31, 2007

Discuss MX Issues Here

I am creating this evergreen post as a way to facilitate discussion of maintenance and equipment topics. There will always be a link to the post from the navigation panel of the blog, so it won't get lost in the mists of time. Please direct any questions or information to a comment on this post.

I hope the blog can be a place to get real-time information that helps avoid last-minute surprises and other inconveniences. However, it will only be as good as the content provided by members.


At 4:11 PM, Blogger John Felleman said...

934 was out of service from 2/5 through 2/9 because of a "not charging" squawk and a dead battery. If you check out the JPI Graph here you can see what was going on. About 20 minutes before the end of the flight, the battery voltage dropped from 28v to 23v. This is a sure sign that charging stopped, possibly due to a tripped overvoltage protection circuit. After that, the voltage continued to decline gradually to a final value of about 20v at the end of the flight. If this was a simple overvoltage, the pilot could probaby have reset the circuit by turning the ALT side of the master switch off for about 2 seconds and then back on. This would have insured safe flight without loss of electric power and avoided the battery discharge cycle.

I just received a call from the front desk that Mode C was not working on the transponder. I will be following up with the club first thing in the morning.

At 10:51 AM, Blogger John Felleman said...

I failed to post some recent MX issues. I recently started a new job and along with other distractions I wasn't finding time to keep the blog current. It remains my intention to provide up to date status information via the blog. Once again, I encourage any club members to post their observations, comments, or questions here for me and for other members. I support openness in the sharing of this information.

At this time, the aircraft is in full service with all equipment operational. MX was just completed the 100 hour service. The next significant MX event is the annual, scheduled to start on 5/31. To minimize downtime from multiple activities, the WAAS upgrade to the 530 will be done then as well. I estimate a total out of service time of up to three weeks. When the plane comes back, it will feature all the power of WAAS.

At 12:17 PM, Blogger John Felleman said...

For some time the KN64 DME has been erratic. The symptoms I have heard reported are either blank digits in the display or a distance reading which doesn't update. I have asked avionics shops to investigate but to date the results are inconclusive.

The DME is not required equipment, because the GPS can substitute as long as the database has the needed waypoints. In general, there should be no reason to cancel a flight based on DME operability. Of course it is a helpful alternate data souce and a good backup if GPS is not available. For that reason, I will continue to take every reasonable step to get it restored to consistent operation.

If you do fly the aircraft and observe any problems with the DME, I would appreciate details on any symptoms you are able to isolate. The most important thing to check right now is whether when it reports incorrectly there is a reliable signal to the receiver. That can always be checked by monitoring DME on the audio panel. In fact, that is considered standard procedure anytime you are relying on the DME for navigation. As a reminder for those who are a little rusty on instrument procedure, the DME signal is a separate transmission on a different frequency than the VOR. It has its own ID, which is transmitted at a higher pitch than the VOR ID, and only once for each 3 to 4 transmissions of the VOR ID.

Also, the DME ID will be the same whether the unit is tuned locally or using remote channeling from one of the NAV radios. Finally, there is a toggle selector switch below the tranponder which allows for selection of NAV 1 vs NAV 2 when using remote channeling.

At 6:33 PM, Blogger John Felleman said...

04/22/2007: The fuel strainer drain is not draining. The plane is out of service. It should be a quick and simple fix.


Post a Comment

<< Home