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Transponders and GA

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Transponders and GA

Old 3rd Dec 2019, 22:10
  #21 (permalink)  
 
Join Date: Oct 2017
Location: Bressuire
Posts: 116
This thread started with regard to an aircraft on battery power. Transponders are heavy power users and expensive, so impracticable in this case. No one has mentioned the NATS Eva project. The purpose was to identify the need of and specifications for low cost conspicuity: low cost and a low power demand was the overriding aim. FLARM, Trig, funkwerk and Pilotaware have produced an interesting array of units, utilising ADS-B and which do not demand a lot of power. They vary in price between 250 and 2,500.

Perhaps some pilots with a practical knowledge of this stuff may join in, otherwise I would suggest contacting the LAA who have a considerable and necessary expertise.

Last edited by Fl1ingfrog; 3rd Dec 2019 at 22:26.
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Old 4th Dec 2019, 09:25
  #22 (permalink)  
 
Join Date: Jul 2010
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Technology has made quite some progress in recent years. On the one hand, transponders are much less power-hungry since the need for cavity magnetrons disappeared; on the other hand today's batteries store lots more energy per unit of weight. Many gliders carry both Flarm and a real transponder these days, powering both systems from batteries.
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Old 4th Dec 2019, 10:45
  #23 (permalink)  
 
Join Date: Jun 2008
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This thread started with regard to an aircraft on battery power.
My understanding (from TRIG) is that their TT21 transponder when pretty busy consumes about 320 milliamps from a 12 volt battery so a dedicated 7A/h 12V battery when new could, theoretically, keep it going for about 20 hours. In practice batteries don't stay new for long and have lower capacity when cold so you may only get 10 hours per charge. Enough for a day's flying.
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Old 4th Dec 2019, 13:31
  #24 (permalink)  
 
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Must be the language barrier Jan at least Il Duce knew what I meant.
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Old 4th Dec 2019, 14:56
  #25 (permalink)  
 
Join Date: Oct 2017
Location: Bressuire
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Transponders have a major limitation in that they are only a one way informer: Additional and separate equipment is required to read those transmissions from other aircraft. The main purpose of a transponder is to inform ATC. FLARM and the like inform all participants with two way/multi way information by transmitting and receiving at a low cost through its own unique systems but of late also through ADS-B therefore it can be read by all: ATC, fast jets, gliders and microlites including powered parachutes. This seems to me the best way to go particularly for vfr only aircraft who are the most likely to be in the mix.

Last edited by Fl1ingfrog; 4th Dec 2019 at 16:24.
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Old 5th Dec 2019, 12:32
  #26 (permalink)  
 
Join Date: Oct 2007
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So, new one for me...

...flying low (about 2000') in Sudan last week, no radar for a few hundred miles - but the controller knew exactly where we were and our altitude.

ADS-B! The future is here...

Cheers, Sam.
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Old 7th Dec 2019, 02:48
  #27 (permalink)  
 
Join Date: Oct 2010
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Originally Posted by Sam Rutherford View Post
So, new one for me...

...flying low (about 2000') in Sudan last week, no radar for a few hundred miles - but the controller knew exactly where we were and our altitude.

ADS-B! The future is here...
The better future with ADS-B will be no controller required, self separation.
Silvaire1 is offline  

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