Saturday, September 02, 2006

Carrier, No Voice

I regularly fly a variety of aircraft, some new, some old, and some really old. They are all well-maintained and safe, else I wouldn't fly them. The older ones have aged with grace, something I've learned to appreciate as I approach my 5th decade. Most of the radios in the older planes have been replaced at least once. Some older planes have new paint with tired interiors. One newer plane I've taught in looks great inside and out, but for some reason it flies crooked - something is just not rigged right. The more hours I fly, the more sensitive I've become to how a plane is rigged.

I once flew an almost brand new Seminole that refused to be trimmed for level flight. Later that same day, I flew a 25 year old Seminole that didn't look nearly as nice and had a right alternator that liked to spontaneously go off-line, but it was one of the most harmoniously rigged aircraft I've ever flown. It didn't have digital engine gauges or a glass panel, but in the air the plane was a joy to fly. Interestingly, when I commented on the plane's excellent handling characteristics, the pilot with whom I was flying looked bewildered, bored, and blank while replying "I hadn't noticed." I was astounded because to me, flying a well-rigged plane is like having a relaxed, pleasant, and engaging conversation. You say "Let's turn right" and the plane says "Good idea." Nothing seems rushed, no ragged edges, no brute force. Piloting a poorly rigged aircraft is like a continuous, onerous, exhausting tug of war.

The award for the most ill-mannered plane I've flown would have to be a tie between a C152 Aerobat taildragger conversion and a two-seat Gruman Trainer. The Aerobat taildragger flew fine once it was off the ground, while the Trainer was easy to control as long as it wasn't in the air.

One thing that seldom ages well is radio equipment, even though the quality of the radios and intercom is another factor that determines whether or not a airplane is pleasant to fly. And how tired you will feel after flying it. This is especially true of intecoms. A noisy intercom is a real impediment to teaching and to learning. It makes everything harder because you can't communicate as clearly. A bad radio is just as bad, maybe worse.

I flew a 150 with a radio that began to generate a side-tone squeal when transmitting. We couldn't hear the squeal, but everyone else could. At first the squeal was not too bad, but with time it got worse. Almost overnight this plane became well-known to ATC, who understandably was reluctant to deal with us. One day my student called for taxi and was met with several seconds of silence, then the ground controller said "I sure hope that was two aircraft transmitting at once." My student tried again and the controller said they could just barely make out out tail number and asked if we had another radio we could use. I got on the frequency and told them this particular plane had just one radio. The controller's response was "I understand you have just one radio and please don't use that radio again."

It took a while to figure this out, but someone discovered that with the intercom turned off, the radio wouldn't squeal while transmitting. So for a week or so, instructing in this plane involved turning the intercom on and off during flight - off before talking to ATC, on before trying to communicate with the student. Finally, the owner got the plane into the avionics shop and the problem was fixed.

Even ATC is not immune to radio problems. On one occasion I was taxiing a Caravan from Oakland's North Field to the freight ramp on the south field. I was told to change ground control frequencies and checked on with the new controller. What I heard in response was someone transmitting, but only transmitting silence - what is known as carrier wave only, no voice. A variety of problems can cause this, but it's most often due to the microphone coming unplugged or otherwise disconnected. Next, a Southwest jet called ground to push from their gate and again the response was carrier only. Then a FedEx jet called for taxi and got the same response. The Southwest jet called again, and got the same response. At that point, I jumped in and said "The last transmission was carrier, no voice." After a brief pause, we all heard the ground controller clear his throat and then ask the FedEx pilot if he could hear him.


paul s said...

Do any of the controller types reading John's blog know if the your radios are set up such that you can hear a blocked frequency in your headset?

It seems it would take a receiving antenna far away from the transmitter or some other tricky circuit to 'hear' the hetrodyne.


sydost said...

If my own radio is blocking the frequency I can't hear it (as the receiver is cut off during transmission) but I can see whether my radio is receiving, transmitting or neither of those.

In case someone else blocks the frequency the ATC transmitters in my experience usually are powerful enough to still reach the non-blocking aircrafts.

Thanks to John for keeping this very informative blog.

John T said...

John – I have an unrelated question. I’ve enjoyed your blogs for months, and wondered if you have considered going back to flying corporate, charter, freight, airline, etc.? I presume, with your experience, you could find a job without too much difficulty?

Sorry for the off-topic question. I don’t see any way to e-mail you, so hope you don’t mind my posting the question here.

John said...

John T,

Glad you enjoy the blog and I appreciate your comments. I do miss flying freight, but I'm unable and unwilling to accept the pay that these operators offer. The working conditions at the regional carriers is not much better. If I were 25 years old, I might view the situation differently.

There may be some charter flying opportunities for me in the near future, but I don't have anything to report at the moment. Soon, I hope ...

bill said...


Just a question. I have flown 4 different c152 and one was very squirrelly on take off and landing, but fine in the air. Just recently a Cirrus rs22 which was very stable and then I flew a Alarus 2000 and the same thing. All over the place on the ground and fine in the air. So I was wondering what “a well-rigged plane” meant mechanically. These are the only planes I have landed and taken off in and my experience is limited. -bill