By Howard Deevers


Remember all of those instructions we got from our CFI when training for private pilot or instrument rating? The squawk codes: 7700 for emergencies, 7600 for communication failure, or 7500 for hijack. In over 40 years of flying, I have never had to use 7500. I guess that no one really wants to hijack a single engine airplane. You probably will fly your entire aviation career without ever needing one of those squawk codes, but if you do need one, will you remember what to squawk and what procedures you should follow after doing that?

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I have had complete electrical failure in an airplane at least 3 times since I started flying. Usually it is the alternator, or generator, that fails, and then the battery runs down so the radios no longer work. The transponder does not work, either.

A friend of mine in Pittsburgh was telling me about a flight he had in his twin Piper from Chicago, DuPage, to Allegheny County, Pittsburgh. He said that he had filed an IFR flight plan, and before getting outside of the Chicago Departure, he lost the ability to communicate with ATC. He never really found the reason for the loss of communications, but his actions showed that training pays off. The weather was IFR part of the way, with small areas of VFR. He continued his flight, and did squawk 7600, to let ATC know that he was unable to hear or talk to them. He was able to receive VOR signals and flew his flight plan. As he approached the Pittsburgh area, and had the Allegheny VOR tuned in, he received a call from Flight Service over the VOR, with instructions for an approach to Allegheny County Airport. He could acknowledge the receipt of the instructions by pressing Ident on his transponder.

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On one of my flights from Iowa to Pittsburgh I lost all electrical in the plane, a Cessna 172. I was making a planned stop in Fort Wayne, Indiana, and had turned on final for landing. It was night, and all lights just went out. I quickly grabbed a flashlight, turned it on, and handed it to my daughter sitting in the right seat, and told her to hold the light on the instruments for landing. I looked for a light from the tower after we turned off of the runway, but did not see one, so just taxied to the FBO. I did call the tower to check with them and tell them that I had lost all electrical on final. They seemed to be okay with all of that. We stayed the night in Ft. Wayne, got the problem fixed the next morning, and continued on to Pittsburgh later in the day.

With the heat we have here in Arizona, radios can take a beating. Last month, while flying with a student, I heard a “pop,” and saw smoke coming out of my #2 radio. I quickly reached up and turned it off. I knew that it was a capacitor that had failed. My electronics training in the Navy taught me a lot about radio circuits. This had the smell of a capacitor; you learn that from experience.

Since this was not a complete radio failure, we just continued with the flight. The next day, I was able to confirm that it was a capacitor. No need to squawk 7600 or an emergency for that one.

Another time, while flying back to Tucson, I tried to call Approach. I had received the ATIS information and was inbound to land. ATC did not respond to my call. I tried again, still no response. Then I heard ATC respond to another aircraft in my area. I tried again and got no response. Well, for some reason, they are not hearing me. I did squawk 7600 and kept heading for Tucson. About 12 miles out, near I-10 and Marana, ATC called: “Aircraft squawking 7600, if you hear this press Ident.” I did, and they must have seen that. The controller asked if we wanted to land at Tucson Airport, press Ident. We did. Then the controller asked us to change the code to 7601, and continue toward Tucson, for Runway 11L and the Tower would be expecting us. About 5 miles out I tried the Tower frequency, and it worked OK. This was in a Flight School airplane, and I did fill out a report on the problem. Mechanics could find no reason for the failure. Another mystery of electronics.

loss of communication

Early in my instructor experiences, I would also emphasize the Squawk codes to new students during emergency training exercises. One of my students had passed his Private Pilot’s check ride, and now we were to meet at Oshkosh. We agreed to meet at Fond Du Lac, just south of Oshkosh. When I arrived, I found their camp, but no plane. They showed up a bit later in a rented car. They explained that a cylinder had failed on their plane while heading north near Milwaukee. Even though they were talking to Milwaukee Approach Control when the engine “burped,” they switched to 121.5 and squawked 7700. He was shocked to learn that the calls he got on 121.5 asked “where he was.” He thought that everyone would know where he was.

It was then I realized that I had emphasized the emergency frequencies and squawk codes too much. If you are already talking to an ATC facility, keep talking to them. Don't change frequencies. They diverted to Watertown Airport and made a successful landing. They left the plane with a shop there and rented a car to meet me at Fond Du Lac. A cylinder had to be replaced due to a valve that had failed. Everyone was safe, and we all learned something from that experience.

Loss of communications can be an emergency, and more so if you are in IFR conditions. The most important thing to remember is to Fly the Airplane! Don't let loss of communications become a worse condition by taking your attention away from flying the airplane to try to fix a  problem that you may not be able to fix anyway.

Fly safely and look for a safety seminar online, on Zoom, or in person soon. The ARIZONA PILOTS ASSOCIATION has not stopped safety efforts even though we don't meet in person so much at this time. Maybe we will have some “catch up” time in a few months.


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