Basics of a good squawk

Mechanical issues can be obvious: a large blue stain under the wing from a fuel sump valve that leaked all night, a broken strobe or navigation light from hangar rash, or a rough-running engine that doesn’t smooth out after trying to clear fouled spark plugs. However, some are more insidious, such as a periodic drop of 100 rpm during flight or a slight decrease in the aircraft’s performance during takeoff and climb.

It’s easy to squawk a glaring issue, but you might second guess yourself when it comes to seemingly smaller mechanical concerns. Was that momentary drop in rpm the engine or did you bump the throttle? Was the slightly decreased performance during the takeoff and climb a problem with the aircraft? Or was it your piloting—were the throttle and mixture not set properly or were you not pitched for optimal climb? You’ll need to learn how to address the obvious and not-so-obvious problems with an airframe and powerplant mechanic.

After my Cessna 170B came out of its annual inspection, the A&P/IA said that his team had adjusted the magneto timing because it was out of tolerance and that we would notice a slight decrease in performance. My husband flew the aircraft first after annual to note any squawks but didn’t notice a change in performance. Then, I flew the airplane with my husband, our two children, full fuel, and some baggage on a 60-degree-Fahrenheit day. We were loaded but still well under maximum gross weight. However, I could barely lift the aircraft off the runway at my typical rotation speed and got a meager 200 fpm climb. It performed as if I were taking off fully loaded on a humid 90-degree-F day. However, in cruise, I achieved my expected performance.

Strange, I thought. Then I performed two flights out of a grass strip. Each time, I had one light passenger, partial fuel, no wind, and temperatures around 70 degrees F. However, climbout was once again anemic, more like what I have experienced out of that strip on a humid day in the mid 80s. Something was clearly not right; the climb performance was the worst I had experienced in my 13 years of owning the airplane.

I spoke to other Cessna 170 pilots to see what their rate of climb was after takeoff to verify my suspicion that this performance was not correct. We asked the mechanic to take another look at the magneto timing. Sure enough, the timing had been set wrong. The team readjusted it, apologized for the mistake, and now the airplane performs as expected.

Because the mechanic had told us to expect a slight decrease in performance after the annual, it took me three flights to be certain that this new “normal” performance was incorrect. I was also hesitant to squawk it after the first flight because I worried how the mechanic would react to me questioning the adjusted magneto timing. I have been fortunate to work with many experienced A&P/IAs as an aircraft renter and as an owner. They all take pride in their work, methodically explain how things work to me, and care as much about the airplane’s safe operation as I do. I have only worked with one mechanic who berated me, and he lost my business.

Aviation mechanics follow a code of conduct, just like pilots and flight instructors. Mechanics who uphold the code make safety their top priority, strive for excellence in their workmanship, and advance professionalism. They want to know if something is wrong with the aircraft, whether it is obvious or something that just doesn’t seem to be functioning properly. They will listen and work to address your concerns, even if it means double checking their own work. Anyone who doesn’t respond to you in a professional manner or dismisses your concerns isn’t worth your business. This is true whether the aircraft in question is yours or one you rent.

I had the opportunity to fly a Cessna 150 from the Anchorage area to the Brooks Range in northern Alaska with an aviation missionary group. As I was preflighting the aircraft before the flight north of the Arctic Circle, I noticed several discrepancies that I wanted to have checked before leaving. The A&P/IA walked through each squawk with me and addressed the ones that needed to be fixed. Even though the team was busy before leaving, he took his time, made sure I felt comfortable, and thanked me for bringing each item to his attention. He reassured me it was OK to squawk all those items even at what some might have thought was an inconvenient time, and he reminded me his job was to make sure the aircraft was safe and airworthy—and that it was important I felt confident in that.

When we squawk possible issues, we need to make sure we are professional in our approach as well. This is true whether you talk to a mechanic in person about your aircraft or write up a squawk as you check a rented aircraft back in at an FBO. Here are some key points to include when describing a mechanical problem—remember to be specific and provide details.

Date and time you discovered the problem. This provides a starting point for the mechanic. If multiple people fly the airplane, he or she can talk with others to see if they had noticed the issue as well to try to determine how long the problem has persisted.

Phase of flight during which you found it. Did the issue present itself during the preflight, runup, takeoff, cruise, approach and landing, or postflight phase? This can provide helpful information. For example, noting the smell of fuel occurring only during descent and approach to landing can help a mechanic track a leak in the lines.

Name of the affected component(s). If the problem is obvious and you know the name of the part(s) involved, use the exact name. For example, “right wing strobe light is smashed,” “left wing inboard rear fuel sump is wet and there is a blue fuel stain under it on the hangar floor,” or “engine develops 200 rpm less on takeoff roll.”

Detailed description of the problem. When you are squawking a potential problem, include as many details as possible. If the issue pertains to aircraft performance, include pertinent information regarding the weather conditions; change in rpm, takeoff, climb, or cruise performance; fuel or oil consumption change; flight control handling characteristics; and any differences in the sound of the aircraft. If the issue is a strange sound, do your best to describe it to the mechanic. Note whether the problem is consistent or intermittent.

If you are unsure whether the problem is purely mechanical or the way you are operating the aircraft, think through how the controls were set each time you experienced the problem. Was everything set properly? Were you flying at correct climb or descent angles and at the speeds indicated in the pilot’s operating handbook? If so, the issue might be mechanical. Talk through how you were operating the aircraft when you noticed the problem. This could provide helpful information to the mechanic.

The more detailed information you provide, the better equipped mechanics will be to trace and address the problem. Providing specific information with a high level of detail will not only show your level of professionalism but will also demonstrate respect for the mechanics with which you will be working. Doing so will show that you respect their time and want to be a team player in ensuring the aircraft is safe and airworthy. FT