Random thoughts 2

[Bill Daniels]

Is it legal/possible/reasonable to install just Mode A transponder (No
altitude reporting)?

Whenever I hear "Traffic 12 O-clock 3 miles, altitude unknown" I look
EVERYWHERE. ahead. Might this provoke more visual scanning by aircraft
crews which could spot gliders without transponders in the same gaggle? A
case of one protecting all?

As a side benefit this would avoid the 24 months Mode C altimeter/encoder
check.

Bill Daniels

[[email protected]]

Bill Daniels wrote:
> Is it legal/possible/reasonable to install just Mode A transponder (No
> altitude reporting)?
>
> Whenever I hear "Traffic 12 O-clock 3 miles, altitude unknown" I look
> EVERYWHERE. ahead. Might this provoke more visual scanning by aircraft
> crews which could spot gliders without transponders in the same gaggle? A
> case of one protecting all?
>
> As a side benefit this would avoid the 24 months Mode C altimeter/encoder
> check.
>
> Bill Daniels

Sure, anything is possible/ and/or reasonable. As far as legal goes,
remember if you have an instrument of any kind installed, you are
required by regulation to have it signed off by an A/P in your aircraft
log book. Additionally some reference to weight and bal. should also
be noted even if it's only to say, "no significant weight change." If
you put a transponder in your glider - either with or without an
encoder - it needs to be calibrated and so noted in your aircraft log
book. You are then required to have checked every twenty-four months.
If you are going to put a transponder in the glider, then spring for an
encoder - In for a penny, in for a pound and all that. Without the
encoder ATC as well as TCAS only gets azimuth and range. With the
encoder you get the third demension, altitude.
Sure beats ending up in Denver as a pitot cover on a B-767!

Billy Hill, Zulu

[flying_monkey]

wrote:
.. . . snip . . .
> If you put a transponder in your glider - either with or without an
> encoder - it needs to be calibrated and so noted in your aircraft log
> book. You are then required to have checked every twenty-four months.
> If you are going to put a transponder in the glider, then spring for an
> encoder - In for a penny, in for a pound and all that. Without the
> encoder ATC as well as TCAS only gets azimuth and range. With the
> encoder you get the third demension, altitude.
> Sure beats ending up in Denver as a pitot cover on a B-767!
>
> Billy Hill, Zulu

Zulu,

Having owned a few junky older airplanes (like old Bonanzas) with only
Mode A transponders, I can't recall any requirement for calibration or
any recurrent inspection of these. If you're flying IFR, you have to
have a pitot/static check every two years, and if you have Mode C, you
have to have the encoder calibrated, but I wasn't aware of anything
other than that.

Ed

[BTIZ]

91.413(a) requires 24 month inspection of any transponder to be used in
airspace defined by 91.215

It makes no reference to VFR or IFR flight.

BT

"flying_monkey" > wrote in message
oups.com...
>
> wrote:
> . . . snip . . .
>> If you put a transponder in your glider - either with or without an
>> encoder - it needs to be calibrated and so noted in your aircraft log
>> book. You are then required to have checked every twenty-four months.
>> If you are going to put a transponder in the glider, then spring for an
>> encoder - In for a penny, in for a pound and all that. Without the
>> encoder ATC as well as TCAS only gets azimuth and range. With the
>> encoder you get the third demension, altitude.
>> Sure beats ending up in Denver as a pitot cover on a B-767!
>>
>> Billy Hill, Zulu
>
> Zulu,
>
> Having owned a few junky older airplanes (like old Bonanzas) with only
> Mode A transponders, I can't recall any requirement for calibration or
> any recurrent inspection of these. If you're flying IFR, you have to
> have a pitot/static check every two years, and if you have Mode C, you
> have to have the encoder calibrated, but I wasn't aware of anything
> other than that.
>
> Ed
>

[[email protected]]

Bill Daniels wrote:

>
> As a side benefit this would avoid the 24 months Mode C altimeter/encoder
> check.
>
> Bill Daniels

I had my Mode C transponder in for it's 24 month checkup in April.
Fifty bucks!

How much are you paying for tows?

Matt Herron

[Eric Greenwell[_1_]]

BTIZ wrote:
>
> BT
>
> "flying_monkey" > wrote in message
> oups.com...
>> wrote:
>> . . . snip . . .
>>> If you put a transponder in your glider - either with or without an
>>> encoder - it needs to be calibrated and so noted in your aircraft log
>>> book. You are then required to have checked every twenty-four months.
>>> If you are going to put a transponder in the glider, then spring for an
>>> encoder - In for a penny, in for a pound and all that. Without the
>>> encoder ATC as well as TCAS only gets azimuth and range. With the
>>> encoder you get the third demension, altitude.
>>> Sure beats ending up in Denver as a pitot cover on a B-767!
>>>
>>> Billy Hill, Zulu
>> Zulu,
>>
>> Having owned a few junky older airplanes (like old Bonanzas) with only
>> Mode A transponders, I can't recall any requirement for calibration or
>> any recurrent inspection of these. If you're flying IFR, you have to
>> have a pitot/static check every two years, and if you have Mode C, you
>> have to have the encoder calibrated, but I wasn't aware of anything
>> other than that.

> 91.413(a) requires 24 month inspection of any transponder to be used in
> airspace defined by 91.215
>
> It makes no reference to VFR or IFR flight.

I can't find any reference in 91.413(a) to encoder calibration, and when
I have the required 2 year test done, only the encoder reading at field
elevation is checked. So, I don't think the encoder calibration check is
required for VFR operation. Do you know of a regulation requiring it?

--
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

www.motorglider.org - Download "A Guide to Self-launching Sailplane
Operation"

[BTIZ]

"Eric Greenwell" > wrote in message
news:chOJg.10062$XD1.1965@trnddc01...
> BTIZ wrote:
>>
>> BT
>>
>> "flying_monkey" > wrote in message
>> oups.com...
>>> wrote:
>>> . . . snip . . .
>>>> If you put a transponder in your glider - either with or without an
>>>> encoder - it needs to be calibrated and so noted in your aircraft log
>>>> book. You are then required to have checked every twenty-four months.
>>>> If you are going to put a transponder in the glider, then spring for an
>>>> encoder - In for a penny, in for a pound and all that. Without the
>>>> encoder ATC as well as TCAS only gets azimuth and range. With the
>>>> encoder you get the third demension, altitude.
>>>> Sure beats ending up in Denver as a pitot cover on a B-767!
>>>>
>>>> Billy Hill, Zulu
>>> Zulu,
>>>
>>> Having owned a few junky older airplanes (like old Bonanzas) with only
>>> Mode A transponders, I can't recall any requirement for calibration or
>>> any recurrent inspection of these. If you're flying IFR, you have to
>>> have a pitot/static check every two years, and if you have Mode C, you
>>> have to have the encoder calibrated, but I wasn't aware of anything
>>> other than that.
>
> > 91.413(a) requires 24 month inspection of any transponder to be used in
> > airspace defined by 91.215
> >
> > It makes no reference to VFR or IFR flight.
>
> I can't find any reference in 91.413(a) to encoder calibration, and when I
> have the required 2 year test done, only the encoder reading at field
> elevation is checked. So, I don't think the encoder calibration check is
> required for VFR operation. Do you know of a regulation requiring it?
>
> --
> Change "netto" to "net" to email me directly
>
> Eric Greenwell - Washington State, USA
>
> www.motorglider.org - Download "A Guide to Self-launching Sailplane
> Operation"

Eric, you are correct.. the encoder for altitude calibration is not in
91.413(a), that part is in 91.411 and 91.411 only refers to IFR
requirements, not VFR.

The 91.413(a) check verifies that the 4096 code dialed in is the code
transmitted and has nothing to do with altitude.

VFR only aircraft require 91.413 every 24 months..
IFR capable aircraft require 91.413 and 91.411 every 24 months..

So if you have the encoder and plan to go into Class A airspace... is the
91.411 required in a VFR only aircraft?

It's all part of the same check.. when you get the 91.413 done, and you have
an encoder, get the 94.411 done. The 91.411 also includes a pitot static
check.

BT