SSA petition to allow transponder to be turned off

Second, a recollection: it's my recollection that ATC radar is
designed to filter out slow-moving targets.

That's primary radar, because of ground clutter problems. It would be a
most unusual situation to eliminate a transponder return. They certainly
don't do it out here in the Pacific Northwest - I've asked.


I've asked to, not quite as northwest as you are. The answer I got is
it depends on how the controller sets up there radar. At most Class C
airports there probably is no filter turned on. At larger airports
they might turn it on to eliminate the returns from aircraft taxing on
the ground. I was also told the can select the speed at which it will
filter the return but typically they might set it up for 25kts.
Typically they have the primary radar turned off unless we tell them
there are gliders or non-transponder equipped aircraft in the area.

Brian

your answer was 100% exactly why they have made the rule......
tim


"Mark James Boyd" wrote in message
news:4039b164$1@darkstar...
In article ,
Tim Mara wrote:
now, I am not going to try to justify the cycle period, and in fact this
can
vary from country to country, and even most manufacturers will probably
say
the 120 day cycle is too frequent for our typical use, but I can
understand the FAA rule on this, and anyone who doesn't see the reasoning
is
why they have the rule...
plain and simple, if it were legal to wear an out of date parachute,
would
you, or anyone else bother to have it inspected or repacked?? I rather
doubt
it....in fact you're already suggested you wouldn't...

There's no rule requiring me to change my tidy-whities every week
either,
but I DO IT! :P For health reasons, you know... Same for a chute.
I wouldn't just sit on the thing for 12 years and drip jelly on it
and drag it through the dirt all day and think it would open. But
if it's my own G*****n chute in a G*****n single-seat glider,
whose business is it anyway?

Rules are never a simple matter or what's right for the masses, but made
because some one or a few people have done something that was
questionable,
or wrong. If we were all perfect, and always right we'd have far fewer
rules, regulations and restrictions....
tim

A coupla guys weighing in heavy on an expired reserve on
a tandem skydiving jump is a hell of a long way from me
in my itsy-bitsy glider wearing an emergency chute I don't even
intend to use. Who'll convince me that the extra safety
of having the more frequent repack outweighs the lack of safety
when I fly twice without the chute each year (while I wait for
the packer to send it back)?

In the UK the recommended repack period is 6 months.
It is only a recommendation, it is not an offence to
fly with a parachute which is out of repack.
The problem with this sort of requirement that the
rules are drawn up for the worst case scenario. A club
parachute which is worn by many people all day and
everyday, and is subject to a high degree of wear and
tear requires regular inspection, and I would be the
first to say that this is good. You do want it to work.
Compare that with my parachute, lives in its bag, not
thrown around, worn perhaps one or twice a week, does
that require the same intensive maintenance? The rules
say yes, in practice is safety compromised at all if
the period between repacks is longer. Most riggers
I have spoken to say no.
Given the choice between sitting on a cushion which
will not protect you from the impact of a crash and
sitting on a serviceable chute which just happens to
be a day over it's due repack I know what I would choose.

At 14:30 23 February 2004, Tim Mara wrote:
your answer was 100% exactly why they have made the
rule......
tim


'Mark James Boyd' wrote in message
news:4039b164$1@darkstar...
In article ,
Tim Mara wrote:
now, I am not going to try to justify the cycle period,
and in fact this
can
vary from country to country, and even most manufacturers
will probably
say
the 120 day cycle is too frequent for our typical
use, but I can
understand the FAA rule on this, and anyone who doesn't
see the reasoning
is
why they have the rule...
plain and simple, if it were legal to wear an out
of date parachute,
would
you, or anyone else bother to have it inspected or
repacked?? I rather
doubt
it....in fact you're already suggested you wouldn't...

There's no rule requiring me to change my tidy-whities
every week
either,
but I DO IT! :P For health reasons, you know...
Same for a chute.
I wouldn't just sit on the thing for 12 years and
drip jelly on it
and drag it through the dirt all day and think it
would open. But
if it's my own G*****n chute in a G*****n single-seat
glider,
whose business is it anyway?

Rules are never a simple matter or what's right for
the masses, but made
because some one or a few people have done something
that was
questionable,
or wrong. If we were all perfect, and always right
we'd have far fewer
rules, regulations and restrictions....
tim

A coupla guys weighing in heavy on an expired reserve
on
a tandem skydiving jump is a hell of a long way from
me
in my itsy-bitsy glider wearing an emergency chute
I don't even
intend to use. Who'll convince me that the extra
safety
of having the more frequent repack outweighs the lack
of safety
when I fly twice without the chute each year (while
I wait for
the packer to send it back)?

Finbar wrote:
The reason I asked about what happens if you turn off a transponder in
flight was that I imagine most/all the pilots who have equipped their
gliders with them are doing exactly that, i.e., turning off the
transponders when they don't feel they're necessary. It's sensible,
but it's illegal. Nobody's been busted so far, but I wonder... About
10-15 years ago we had a brief period when the FAA suddenly started a
get-strict policy and enforcing all these "petty" rules, and AOPA and
the aviation press were warning pilots not to talk to ANYONE from the
FAA without a lawyer present. Remember the days when some airline
pilots filed a NASA form after every flight, just in case? Cooler
heads prevailed, and our FAA field personnel were allowed to go back
to doing their jobs promoting safety instead of playing "gotcha" with
obscure regulations, but who knows what the future will bring, and who
knows how many of those disappearing transponders will have been
digitally recorded for the benefit of some enterprising career-minded
young investigator? The trouble with bad laws is that sooner or later
some dimwits show up and enforce them. It's not like it hasn't
happened before. And unlike flying with an out-of-date chute, when
you turn off a transponder your crime is broadcast to the world (or,
technically, your compliance with the law is no longer broadcast!).

I'm told by SSA officials and others that talk to FAA people frequently
about airspace issues that the FAA knows glider pilots turn off their
their transponders sometimes, and the FAA doesn't care about that.
Mainly, they are just really happy the pilot is willing and able to
carry one.

I'm sure ATC doesn't care, either, if a VFR transponder signal
disappears 50 miles from their Class B airspace, as long as it was
heading away from them. Signals disappear for various reasons, such loss
of radar coverage and equipment failure. They aren't going to send out a
posse to get you; mainly, they are just glad you have one when you are
close to them.

To the best of my knowledge, this exemption seems to be a good one for
glider pilots. It will legalize what some of us already do, and make
putting in a transponder slightly more interesting to those that adhere
strictly to the rules. Safety may increase ever so slightly. The biggest
benefit might be we won't have to have talk about the issue any more,
and can go back to other things.
--
-----
change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Experts, correct me where I'm wrong.

1. An operating transponder, not being interrogated, is simply a receiver
with a low current drain.
2. When interrogated by a ground radar or TCAS, a transponder transmits a
short "squitter" at 175 or 250 watts which is a BIG current drain.
3. Flying in an area with many interrogations per minute is likely to be a
congested area where the transponder is needed and a wise pilot would keep
it on despite the current draw.
4. Flying away from a congested area toward a remote area with few
interrogations, the transponder automatically cuts back on its current draw
by operating less and less as a transmitter and more as a receiver.

So, where is the need to turn it off? Doesn't the transponder effectively
manage its own current draw to match the level of congestion? Move away
from congested areas and the current draw is minimal. I haven't read of a
case where the transponder is sucking batteries flat and if that happened,
how much additional battery capacity is needed to keep it running for the
whole flight? (I can remember pilots carrying car starting batteries to run
a vacuum tube radio. No imaginable suite of avionics would draw that much
current today.)

So, aside from the cost of a transponder installation, what is the concern?

Bill Daniels

p.s. Having suffered a couple of alternator failures at night in hard IFR
with single engine airplanes, I became very interested in the current draw
of each bit of avionics. My calculations showed is that if the aircraft
battery is in good condition and fully charged at the point where the
alternator failed, and the pilot swiftly switches off the alternator field
with the split master, the battery will run a full IFR panel longer than the
fuel will last. I tested that calculation and it proved true with good
safety margins.

Tim,

Let's get to the part about me being reckless first: you wrote

"if it were legal to wear an out of date parachute, would
you, or anyone else bother to have it inspected or repacked?? I rather
doubt
it....in fact you're already suggested you wouldn't..."

I didn't suggest any such thing, and please don't you suggest that
about me. In fact, in my post I said this wasn't the point, and I
said my chute is always properly packed.

On the other hand, you yourself just suggested that the 120-day
requirement is overkill.

Now to the part where I'm still feeling like I just stepped into the
middle of Alice Through The Looking Glass:

Tim Mara

just posted a statement

supporting

a regulation that,

under certain commonplace circumstances,

requires

a pilot in command

to substitute

a seat cushion for a parachute

when going flying.


TIM MARA supports that? As a SAFETY measure?

Boy, that just can't be. What was in that coffee I just drank?

Wow.

Bill Daniels wrote:
Experts, correct me where I'm wrong.

1. An operating transponder, not being interrogated, is simply a receiver
with a low current drain.

Not so low: my Becker (175 W version), with the ACK 30 encoder, draws
about 400 ma. In very cold weather (winter wave flying), this rises
50-100 ma because of encoder heating.

2. When interrogated by a ground radar or TCAS, a transponder transmits a
short "squitter" at 175 or 250 watts which is a BIG current drain.

True, though internal to the instrument; the battery and wiring won't
see a spike.

3. Flying in an area with many interrogations per minute is likely to be a
congested area where the transponder is needed and a wise pilot would keep
it on despite the current draw.

I agree, but the increase is only 130 ma at 1200 interogations/sec! The
increases I've seen in Southern California are more like 30 ma, and just
a few milliamps when there are only 3 or 4 radars hitting it.

4. Flying away from a congested area toward a remote area with few
interrogations, the transponder automatically cuts back on its current draw
by operating less and less as a transmitter and more as a receiver.

So, where is the need to turn it off? Doesn't the transponder effectively
manage its own current draw to match the level of congestion? Move away
from congested areas and the current draw is minimal.

It's still 400 ma with the encoder, a significant but not overwhelming
amount for the typical 7 amphour battery. 400 ma may be what all the
other instruments are pulling, so it cuts the battery life in half.
Still, a 7 AH battery should easily last 7+ hours.

I haven't read of a
case where the transponder is sucking batteries flat and if that happened,
how much additional battery capacity is needed to keep it running for the
whole flight? (I can remember pilots carrying car starting batteries to run
a vacuum tube radio. No imaginable suite of avionics would draw that much
current today.)

So, aside from the cost of a transponder installation, what is the concern?

Having a transponder on for the entire flight likely means the pilot has
to charge it (or put in a different one) everyday, rather than every
other day. The battery may need replacing more often, say every 3 years
instead of 4 or 5. Gliders with batteries smaller than 7 AH probably
could get by with, say, a 4 AH battery by using the transponder for only
a couple of hours instead of full time.

I don't think these concerns are important if you think you need a
transponder, and I suspect it's the ~$2000 cost that stops most people,
plus the $50-$70 every two years to have it tested.

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

Eric Greenwell
Washington State
USA

Bill Daniels wrote:

Experts, correct me where I'm wrong.

I'm not an expert, but I'll answer anyway, this is RAS, after all.

1. An operating transponder, not being interrogated, is simply a receiver
with a low current drain.
2. When interrogated by a ground radar or TCAS, a transponder transmits a
short "squitter" at 175 or 250 watts which is a BIG current drain.
3. Flying in an area with many interrogations per minute is likely to be a
congested area where the transponder is needed and a wise pilot would keep
it on despite the current draw.
4. Flying away from a congested area toward a remote area with few
interrogations, the transponder automatically cuts back on its current draw
by operating less and less as a transmitter and more as a receiver.

So, where is the need to turn it off? Doesn't the transponder effectively
manage its own current draw to match the level of congestion? Move away
from congested areas and the current draw is minimal.

You are assuming that areas of low traffic are also areas with few
interrogations, which is not necessarily true. In my case, the primary
concern is the area within 30 miles or so of Reno, where there is high
likelihood of encountering airliners in the 10 to 18K foot range.
Outside of the immediate area of Reno, my transponder still gets
interrogated, due to enroute and military radar.

I haven't read of a case where the transponder is sucking batteries flat
and if that happened, how much additional battery capacity is needed to
keep it running for the whole flight?

Our Duo came standard with dual 7ah batteries. A combination of an
LNAV, GPS-NAV, radio, and transponder sucks a single 7ah battery dry in
a little more than 4 hours. We were replacing the batteries roughly
once per year, since some of the partners (not me, of course) would
forget to either switch batteries or turn off the transponder before
draining the first battery completely. We switched to using dual 12ah
batteries, and the problem appears to have gone away.

Marc

Now this is a little silly, but are there any manufacturers that
make modern Mode "A" transponders (no altitude encoding)?
I've seen a portable one (battery operated) that looked pretty
old.

I think this is TSO-C74b, ref 91.215(a). I just wonder how much
of the extra price and inspection is just the mode "C" part of modern
transponders.

I wonder how many more owners would install a mode "A" if it only
drew 50mA max, was the size of a cell phone, required no recurring
inspection, and cost "about $100" (quote from Rain Man).

Better than nothing. And allows you into A,B,C by deviation
request. And gives at least lateral avoidance to airliners.

Maybe a market here to compete with the over-capability of the
mode "C". Better is the enemy of good, especially when talking
about optional equipment.

In article ,
Andy Durbin wrote:
One year at Hobbs, New Mexico, every contestant's parachute was
checked for currency by an FAA inspector. The infamous "ramp check".
Don't know how many he found but he probably had a nice day away from
the office.

NSF, the organizer of contests at Hobbs, now has a rigger available
before most (all?) contests and he does a lot of business.


Andy (GY)

Hmmm...no doubt chutes were required for the contest, and formation
flight was definitely going to happen. Another benefit of
the inspection was it made the rigger available the following
year for a bunch of pilots who were "on the fence."

This is a situation where I might go the other way. Just
like seat belts or helmets being inspected and required
during a sanctioned car race, there is a group of organizers
who have a vested interest in each pilot having safety
equipment.

I'm willing to bet the FAA "ramp checker"
didn't do this AFTER the flight, with a subsequent violation,
but before the flight as a prevention measure and no violation.
The inspectors I've met have been hired for their wisdom,
experience, and judgement, and not for their ability to
meet a quota...

This brings up one other marginal disadvantage to increasing
repack cycle: fewer qualified and paid riggers available.
A double-edged sword.

I'm still going to say the 6 month cycle is better (improving
technology has its advantages), and chute wearers in
single seaters shouldn't generally have
a repack requirement or violation by the FAA.
But I'd certainly support
contest organizers requiring "current" chutes if it
reduced their liability (just like sanctioned car races
require certified helmets and dated, refilled
fire extinguishers).

I'll add that in Calif., fire extinguisher refill
cycles have gone from 1 to 5 years (maybe 6?). Again,
improving technology eventually should be recognised and
the benefit passed on to the user/consumer...