Do I need mode S

[maule-m7-260]

I have a small plane with mode C and IFR equipped and want to fly to Friedrichshafen in the airways. I am out of touch with SSR requirements where exactly is mode S designated airspace?

Maule Pilot

[achimha]

Mode S is mandatory in Germany where a transponder is mandatory. Unfortunately, the area around Friedrichshafen is classified as one of the very few TMZs (transponder mandatory zones) in Germany. The reason is that Friedrichshafen has quite a lot of big birds doing IFR but when leaving / before entering the control zone, you're in airspace E.

It is possible to request an exemption with the German AIS ([phone]). Usually not problem but in this case, I'm a bit pessimistic. You might consider one of the other airfields with shuttle bus service (e.g. Markdorf or Konstanz).

PS: No IFR arrivals at Friedrichshafen below 1.6t during the show.

PPS: Don't tell them you don't have a Mode S capable transponder, rather say that it's out of service and your backup is Mode C only.

PPPS: On every 2nd flight I hear ATC saying something like "I only see a Mode C signal from you, just for your information, continue".

[Johnm]

If you want to fly airways you need a Mode S transponder and BRNAV capability

[Rory Dixon]

According to the German AIP you need mode S:

• in class C and D airspace (not CTR) (there is no class A and B airspace in Germany)
• in a TMZ
• at night in controlled airspace (so basically above 2.500 ft)
• and when flying a motorized aircraft at or above either 5.000 ft ASL or 3.500 ft AGL, whichever is higher.

achimha has mentioned some practical details.

[soaringhigh650]

In the UK, flight within the London TMA requires mode S.

[maule-m7-260]

Mode S

Thanks for the helpful input

Maule pilot