Lost comms after radar vector

"John R Weiss" wrote in message
news:_LWOb.84380$Rc4.305921@attbi_s54...
"Ron Natalie" wrote...

Squawk 7700 briefly (15 seconds?) to get the attention of ATC, and
to
give
some notice of your intention to exercise your PIC emergency authority
to
"bend"
the regulations.

Not necessary. If squawking anything is working, 7600 will get their
attention just
find. You don't need to give them any such notification.

I don't know the current state of the art of ATC radars. However, the
7700/7600
switch was a part of the Navy Instrument Flight Manual as late as 1994.
The
rationale was that not all ATC radars had the same level of alerting for
7600
squawks as 7700, and/or that the alert might be manually disabled.

If all ATC radars now have the same level of alert for a 7600 squawk, then
7600
only makes sense.

7700 for one minute, followed by 7600, is one of the "wrong" answers in two
questions on the IFR knowledge test, and I always assumed that was because
it is a known incorrect or obsolete practice. However, one of the questions
specifies "you do not exercise emergency authority", so isn't exactly
appropriate to the specified scenario.

-- David Brooks

"David Brooks" wrote in message
...
"John R Weiss" wrote in message
news:_LWOb.84380$Rc4.305921@attbi_s54...

snip
7700 for one minute, followed by 7600, is one of the "wrong" answers in
two
questions on the IFR knowledge test, and I always assumed that was because
it is a known incorrect or obsolete practice. However, one of the
questions
specifies "you do not exercise emergency authority", so isn't exactly
appropriate to the specified scenario.

It apears Weiss needs some remedial training.

Roy Smith wrote in message ...
My instructors answer was this: when lost comms is noticed and no
attemp to establish alternate comms works, then proceed to the outer
marker of the ILS22 approach (VICCI) and hold as diagrammed until your
flight planned expected arrival time, then shoot the approach.

That's the correct book answer. Unfortunately, it's the wrong real-life
answer.

Roy,

I'm not persuaded it's even the correct book answer.

I had a lost comm once. We lost the ability to transmit (turned out to
be a stuck relay in the audio panel) immediately after takeoff. We
could hear ATC, but they could not hear us

Interesting -- any details about what model of audio panel? Did
it block both hand mic and headsets?

Obviously, what you did wrt shooting the ILS was 100% the right
call for your circumstances but I'll toss a couple different circs
out.

We had a brief lost comm IFR in IMC. It was caused by me. In
response to smoke coming out of the panel and a strong smell of
burning, I advised ATC we were going off freq due to smoke in the
cockpit and shut off the electrical system.

Plan A if the smoke didn't stop was to turn left, fly out over
the ocean, do an emergency descent and fly back in to ditch on
a beach.

Plan B if the smoke stopped was to remain at our current altitude
and procede to known VMC ahead of us.

The smoke stopped and we eventually completed the flight with
most of the plane's electrical equipment operating and normal
comms.

We were offered Plan C (shoot an ILS at the nearest airport)
but shooting an approach to minimums or below with a questionable
electrical system simply wasn't on our menu.

My husband had a lost comm VFR on the very first flight I took with
him when he'd first gotten his license (my 2nd flight in a small
plane). It was caused by electrical failure. The ability to
transmit on the radios went first, followed by the ability to
receive followed by the rest of the electrical system. We were
VFR but if we'd been IFR, I don't think shooting an ILS would
have been a bright call there either.

BTW, if you ever think you're going to lose comm (say, the lights are
slowly diming and the radios are getting crackly), be pro-active. Make
a plan and tell the controller what it is while you still can so
everybody's on the same page.

Concur!
Sydney

In article ,
(Snowbird) wrote:

I had a lost comm once. We lost the ability to transmit (turned out to
be a stuck relay in the audio panel) immediately after takeoff. We
could hear ATC, but they could not hear us

Interesting -- any details about what model of audio panel? Did
it block both hand mic and headsets?

I don't remember what model. We tried both headsets and the hand mike.
I'm not 100% sure it was in the audio panel per-se. Might have been in
the intercomm box, but it was definately a problem with a relay, and
definately in the "audio stuff".

..

I don't know the current state of the art of ATC radars. However, the 7700/7600
switch was a part of the Navy Instrument Flight Manual as late as 1994.

It's been gone from the AIM longer than that I believe.

"David Brooks" wrote in message ...
7700 for one minute, followed by 7600, is one of the "wrong" answers in two
questions on the IFR knowledge test, and I always assumed that was because
it is a known incorrect or obsolete practice.

Should we fly triangular patterns too?

Don't forget the dropping chaff gambit.

Jim


"Ron Natalie"
shared these priceless pearls of wisdom:

-
-"David Brooks" wrote in message
...
- 7700 for one minute, followed by 7600, is one of the "wrong" answers in two
- questions on the IFR knowledge test, and I always assumed that was because
- it is a known incorrect or obsolete practice.
-
-Should we fly triangular patterns too?



Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

"Ron Natalie" wrote...

I don't know the current state of the art of ATC radars. However, the
7700/7600
switch was a part of the Navy Instrument Flight Manual as late as 1994.

It's been gone from the AIM longer than that I believe.

My '98 AIM (only one I have at home) says "ATC service will be provided on the
basis that the pilot is operating in accordance with FAR Part 91.185." It also
says squawk 7600 when operating NORDO.

So, it still leaves open the question of squawk if the pilot chooses to deviate
from 91.185 via 91.3(b) (emergency authority) or per AIM 6-4-1.a ("exercise good
judgement"); and is counter to the 'change back to assigned squawk' preference
expressed by the resident controllers.

The question also arises as to when the "filed" ETE is "amended" by ATC in the
OP's original scenario, or similar situations. If in radar contact the entire
route, the pilot is not required to update his ETE if he maintains filed TAS.
When the tailwind significantly changes the ETE, on what basis would a pilot be
able to predict what ATC might "expect"?

I agree with a previous poster that IF the pilot has already been talking with
Approach and has received a vector toward an IAF or ILS intercept, it is
reasonable to expect to commence approach on arrival. However, what if comm is
lost on a center freq, in IMC and relatively near the destination? What is a
"reasonable" time to be holding over the IAF, from the ATC perspective?

"Mike Ciholas" wrote in message
m...
I had a "discussion" with my instructor about lost comms in IMC after
a radar vector. To illustrate, consider this scenario (gratuitously
enhanced with specifics):

Depart BJC (Boulder, CO) for a flight to EVV (Evansville, IN). You
expect the flight to take 4:30. You depart at 1200Z. Once airborne,
you get established on a clearance route and you realize that the
tailwinds are much stronger than forecast. After 3 hours have passed,
you find the GPS saying EVV is only another 30 minutes enroute (thus
the flight now should take 3:30 instead of 4:30). You get the ATIS,
using ILS RWY 22, relatively low IMC conditions at EVV. ATC then
gives you a radar vector to bias your flight path north for the
approach. At this moment, you loose comms. All attempts to establish
comms are in vain. The weather is also low IMC in every direction.


You should have been told what you were getting vectors for. As someone
else said - I am not sure what "bias your flight path" means. You should
not take vectors unless you know what they are for.

I hope I don't ever loose my comms in IMC - it might land on someone...
grin

What do you do?

snip

This is really an academic question because I pretty much doubt anyone
would convince me anything other than landing at my earliest and
safest opportunity would be the right course of action, rules or no
rules to the contrary. In fact, in any lost comm situation, I doubt I
would hold for any reason.

That is scary. What if you lost comms in a hold? Just go to the
destination and shoot an approach? I hope this was just an off-the-cuff
remark and that you really don't mean that. That is what clearance limits
and EFC and EACs are for.


My thinking about ATC response is that
they cannot assume any behavior of a lost comm aircraft, there could
be more wrong than just the lost comms (such as the pilot is
incapacitated and a passenger is flying, thus no behavior is
predictable). So I would think they would vector everyone else away
and hope the plane gets on the ground as soon as possible.


That is why lost comms procedures are well-defined. Everyone should be in
agreement about what to do.



Curious what the group reg gurus and ATC types think about this.

--
Mike Ciholas (812) 476-2721 x101
CIHOLAS Enterprises (812) 476-2881 fax
255 S. Garvin St, Suite B
Evansville, IN 47713 http://www.ciholas.com

Roy Smith wrote in message ...
(Snowbird) wrote:
The towers don't show on the typical handheld or panel GPS

No, but I bet they do show up on the approach plate, if not explicitly,
then at least reflected in the MSA values.

Yes, they're reflected in the MSA values.

I certainly agree with you that ad-libbing an approach is a bad idea,
but as long as you're above the MSA, it's hard to see how you could get
into trouble.

I agree, but there are two big "ifs" which weren't explicit in
the original scenario:
1) you're w/in 25 nm of the navaid on which the MSA is depicted;
we've certainly started getting vectors for the approach more
than 25 miles out at times
2) you're above the MSA. For example, in one local approach I
mentioned, it's typical to vector small aircraft between 2000
and 2400 ft, but there's a tower farm just to the east of the
usual area. The MSA is 3100 ft. You'd need to be what, a good
4 miles out from the marker to intercept below glideslope?

I would think such scenarios (MSA much higher than typical MVAs
used for the approach) are pretty common. But I dunno.

Cheers,
Sydney