Do you know the new ATC equipment code suffix for your airplane?

John Mahany • July 5, 2023

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I bet maybe you don’t. I thought I did, until recently. Did you know that the ATC equipment code suffixes have changed? Yup, they have! In fact, they changed about 4 years ago, in 2019! I’m talking about the suffixes, like /T or /U or /G  ‘codes’ that we used to use for our avionics capability when talking to ATC or when filing a flight plan, as in, a Cessna 150/U? Well, it has changed.

So how did I learn this? Well, I have been aware of it, but I have not been using the new codes, not when flying my Cessna 150. No ATC controllers at SoCal have said anything to me. Nor any of the briefers at LEIDOS, when I have called many times for a weather briefing.

However, recently when I called Leidos, 1-800-wxbrief, for a standard weather briefing, when I initially told the briefer that my Cessna 150 was a ‘/U’, boy he called me out for this and went on a RANT! He spent several minutes reprimanding, like I shoulda known better, oops, and spelling it out in some detail, and all I could say was, sorry, I goofed. No point in arguing. Mea culpa. Yep. But gee, last summer, when flying my Cessna 150 2/3’s of the way across the country to Oshkosh for AirVenture, not one briefer made any mention of this. Hmm. Well, that’s just the way it is.

So, what’s behind this? Well, as I see it, this is due to the introduction of so many new avionics units/devices on the market in recent years; by several manufacturers, and because of so many different GPS receivers now.  And, also because of the many newer displays (glass cockpits) and transponders now, and the varying capabilities of each, the FAA has had to ‘recategorize’ avionics, according to what each does. That’s how I see it. E gads! Hard to keep up.

So, do you know the codes for the airplane you fly? It depends on what avionics you have. Have you seen the FAA form that sort of ‘explains’ this? In the AIM, the ‘flight planning form’ is in the back, in Appendix 4. At the beginning of the Appendix are several pages of explanations. Officially, it’s FAA Form 7233-4-International Flight Plan.

I find it to be confusing! Maybe because I’ve been using the old flight planning form for so long. So, I’ll try and explain a little of it. Very briefly. With thanks to Richie Lengel, and his very popular book ‘Everything Explained for the Professional Pilot’….; instead of the suffix U which was for Transponder with Mode C Altitude Reporting and no DME, if you are flying a single engine airplane, with ‘standard avionics’ including NavCom with VOR/ILS and VHF communications, like many of us, then your equipment code/suffix is now ‘S’. And for the transponder code, now there are three choices; A, C or S. For my 150, it’s now code C. There’s MUCH more to this. But I can see I’m going to have to work on creating a pamphlet to explain this, in more detail, and better.

That’s all for now. I have my work cut out for me.

In the meantime, fly safely!

John

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