Transponders & Gliders

Hi, my name is Hugh, and I’m the reason you need a transponder in your glider.

Jet Traffic and You

My day job is sitting in the left seat of a 50 seat regional jet, flying to glamorous destinations like Dayton, OH, Chattanooga, TN, Roanoke, VA, Columbia, SC and State College, PA. Which, you may notice, happen to coincide with places like Caesar Creek, Chilhowee, New Castle, Perry, and Mifflin. Chances are if you are reading this and regularly fly out of one of those sites, we’ve shared the sky together.

I probably didn’t see you. And the reason I didn’t see you is that you don’t have a transponder.

“BUT I HAVE FLARM!” I can hear some of you yelling. Well, that’s all well and good, but only other people with FLARM can see you. FLARM is wonderful, but it doesn’t talk to TCAS, and in the cockpit of a jet, if we don’t have you on TCAS we probably won’t see you at all.

We’re Going a Lot Faster Than You Think

Let’s talk a little bit about what a normal descent profile looks like for a regional jet. At roughly 30 miles from the destination airport, we are usually at 10.000 feet doing 250 knots. Most of us will hold that speed during visual approaches (and you probably aren’t out flying with us when we are doing instrument approaches) until 10 NM from the field. Our descent rates are usually around 1500-2000 feet per minute during this phase of flight. So...practically speaking, what’s that mean?

It means that if you are relatively stationary to my track of flight (in a thermal for instance) that I’m closing on you at a rate of 1 mile every 15 seconds. This is not a lot of time for either of us to “see and avoid” the other.

Transponders Make You Visible on TCAS

Earlier this year I flew into State College during the contest that was being held in Mifflin, on a ridge day. As a glider pilot myself, I was incredibly excited to have a slight chance to actually watch a glider race in action. I spent the short flight from Washington DC telling the other pilot I was flying with about the contest that was going on and how Mifflin was a Mecca for ridge soaring. I had checked Glideport prior to departure, I knew the task, and where the competitors were likely to be at the time of our arrival. We started looking the instant we got below 10,000 feet.

We saw nothing. Until our TCAS system snatched a target out of the noise that appeared to be on the ridge. That was enough to pick out a single sailplane cruising along the ridge, right where we expected it to be. Then we found another, and another, until we had counted 5 gliders racing along in close proximity to the one individual that happened to have a transponder. We wouldn’t have seen a single one without that TCAS target.

This was a wake-up call to me. My wife’s Discus has a transponder, and it was something we both felt strongly about from a safety standpoint. But it never really hit home just how important it was until I was in the cockpit of an airliner, with another pilot, both of us actively searching for gliders that we KNEW were there.

It’s a “Big Sky”... Until it’s Not

Most of us that have been in soaring for a while have either had a close call with power traffic or know someone that has. Kathy Fosha got close enough to a small turboprop airplane over Texas about 30 miles north of Waco while flying a borrowed Discus that the other pilot told the approach controller “I know I must have hit it”. A transponder would most likely have prevented this, and it definitely would have saved both pilots from losing a few years due to fright.

Jamie Shore, who flies an airliner professionally to pay for his soaring habit, is also a proponent of transponder installation. One of my favorite stories he told me involved him flying his transponder equipped glider near Austin, TX close to one of the arrival routes into the airport there. He was monitoring approach control and noticed that even though he wasn’t talking to them, they were vectoring jet arrivals around his location to ensure separation. He never saw any of them.

Transponders are Safety Equipment, Not Avionics

Most of us wouldn’t dream of crawling into our gliders without a parachute (I personally know two people who have used theirs in anger), and satellite trackers are becoming considered a crucial piece of safety equipment as well. As you spend the winter pondering what upgrades to make to your favorite sailplane in preparation for the 2020 soaring season, put everything else on hold until you have a transponder.

Now, I know there are plenty of “reasons” not to install a transponder, just as there is plenty of “evidence” that the earth is flat. Both standpoints are wrong. Still, I will address the most commonly stated reasons to avoid joining the transponder equipped elite:

It’s too expensive.

It’s less expensive than a midair. It’s ALSO less expensive than:

1)     A new Cleanav

2)     A new LX computer

3)     A new parachute

It draws too much power.

Not really. Sylvia has flown our Discus on 6 hour + flights without switching batteries, while running a transponder, Power Flarm, Cleanav, Cleanav vario, extra Clearnav display, radio, and charging her phone off of a 12v USB outlet. 

I don’t have room in my panel.

Make room.

I don’t want “THEM” to know what I’m doing.

Sorry to break it to you, but “THEY” don’t care what you are doing as long as you aren’t:

1)     Violating the airspace around DC.

2)     Flying through a presidential TFR.

3)     Moving Bolivian Marching Powder across the border.

4)     Running into an airliner full of paying passengers while you were working a thermal “500 feet” below cloud base.

“THEY” will see you in the first three examples with or without a transponder. Guess which one of those a transponder will specifically help you avoid?

As you can see, arguments are feeble and unimaginative, just like a Flat Earther.

Don’t be like them. Install a transponder. The life you save very well could be mine.

Hugh Grandstaff is a Captain and Simulator Instructor for Air Wisconsin Airlines. He has been flying for 23 years in a wide variety of types and categories of aircraft and grew up in an aviation family. Hugh has worked as a deckhand on tugboats, a research assistant at a major university, a navigation and cargo officer on ocean going ships, an executive at a scrap metal processing company, and currently as an airline pilot. Hugh graduated from the U.S. Merchant Marine Academy, and lives with his wife Sylvia (a much more interesting and accomplished pilot than himself) in their tiny house on a small plot of land connected to a grass runway in Alabama. Hugh also served as CD for last summer’s U.S. club class nationals.