Mode C Transponder

Aircraft electrical systems. Generators, both engine and wind driven. Other electrical systems, wiring, fuses, lighting and so on.
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Mode C Transponder

Post by 7AC-JC » Thu Jun 03, 2010 13:03

I'm a student pilot anticipate closing on a 7AC in the near future and had a few questions.
(My check ride will not be in this aircraft.)

It is equipped with a rechargeable battery that powers a handheld radio with external antenna.

Since the aircraft does not have electric, is it safe to say, it will not require a Mode C transponder?

Do any of you have one installed, any how?

If so, what type and how did you install it?

If you do not have one, is there anything particular needed when entering Class D or Class C?

Without a Mode C transponder will I ever be able to establish Flight Following?

Finally, how difficult is it to install one? Would they draw a lot off the rechargeable battery?

Thanks for the help.


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james gevay
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Re: Mode C Transponder

Post by james gevay » Thu Jun 03, 2010 15:56

Please look up 91.215 -3 and you will see that they are NOT required in the Mode C veil, Class A, B and C is different of course.

(3) Notwithstanding paragraph (b)(2) of this section, any aircraft which was not originally certificated with an engine-driven electrical system or which has not subsequently been certified with such a system installed, balloon or glider may conduct operations in the airspace within 30 nautical miles of an airport listed in appendix D, section 1 of this part provided such operations are conducted—

(i) Outside any Class A, Class B, or Class C airspace area; and

Do not get confused and think the Mode C veil is the same as Class B, they are not they are only associated with each other and have different rules.

Thats one of the the things that many pilots after 911 were confused about, the difference between Class B and Enhanced Class B, two totally different airspaces with different rules.
I do not, and I will not install one, as I'm keeping my plane as close to original as possible.
I operate under the Class B around Minneapolis/St Paul and out of one of the Class D airports in the metro area.
You can enter Class D airspace, although the guys in the tower may strongly wish that you had one to make their job a little easier.

Roger Anderson
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Re: Mode C Transponder

Post by Roger Anderson » Thu Jun 03, 2010 17:48

1. There are some transponders available that will run off a battery. Sailplanes use them. 2. As James said, you are exempt from the mode C veil transponder requirement only, not the class B airspace itself. 3. FAR 91.215 gives you the requirements for class C requirements. You can get occasional exemption to enter class C without a transponder but that should be the exception, not the rule. If you operate in class C on a regular basis, you need to get a transponder. 4. Even an aircraft with an electrical system is not require to have a radio or transponder if it doesn not fly into airspace requiring them. It's the airspace type that establishes the requirements, not the type aircraft. 5. You can enter class D airspace if you have a radio and establish communnications with the tower. Again, as James said, a transponder would make the controllers life easier assuming the tower is equipted with brite radar, but not required. 6. No, unless it's an emergency, it is unlikely you will get flight following without a transponder. Current radar just doesn't see primary targets easily, or tracks them with consistence very well. The additional workload on a controller to follow you (and to establish radar contact) would be difficult for what is considered an "addtional service". But then......we don't have our low and slow fun Aeronca flying machines to do any of that. We are a trip back in time.

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Re: Mode C Transponder

Post by joea » Thu Jun 03, 2010 21:58

Do a search on this bulletin board and you will find a thread or two about this. There are several people running around with portable radio's and transponders. Neat idea.

Joe A

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