IFR use of handheld GPS

"Ron Lee" wrote in message
...
"Steven P. McNicoll" wrote:


"Ron Lee" wrote in message
...

A primary reason that handheld/VFR GPS units are not acceptable for
VFR use is that they not not include an integrity capability. That is
essential for IFR ops.


Can you explain why that is so?


Let me ask you a few things.

1) Are you aware that the clocks onboard a GPS satellite can
malfunction?

2) Are you aware that when a malfunction occurs that the users' GPS
unit derived position can drift off by hundreds or thousands of miles?

3) Are you aware that the pilot may well have ZERO indication of that
failure without an integrity functionality in his user equipment?

If your responses are "So," "So," and "So" then I have no desire to
ever fly with you if you are a pilot.


I'm aware that anything can malfunction. I've answered your questions, it's
time for you to answer mine.

I'm aware that anything can malfunction. I've answered your questions, it's
time for you to answer mine.

You have neither answered my questions nor done what I suggested. Why
not?

Ron Lee

"Ron Lee" wrote in message
...

You have neither answered my questions nor done what I suggested. Why
not?


Your "questions" were actually one question. I answered them when I said
anything can malfunction. I'll do what you suggested after you send me
money to pay for the flight.

I'm left to conclude you cannot answer my question.

"Steven P. McNicoll" wrote:


"Ron Lee" wrote in message
...

You have neither answered my questions nor done what I suggested. Why
not?


Your "questions" were actually one question. I answered them when I said
anything can malfunction. I'll do what you suggested after you send me
money to pay for the flight.

I'm left to conclude you cannot answer my question.

I'm left to conclude that you are not a pilot to entrust with anyone's
life. Do you need a reg to tell you not to fly into thunderstorms?
Do you need a reg to tell you not to fly into known icing conditions
with an aircraft not approved for it?

Do as you wish. Just don't take anyone with you should you fall prey
to Darwinism.

Ron Lee

"Ron Lee" wrote in message
...

I'm left to conclude that you are not a pilot to entrust with anyone's
life.


Upon what do you base that conclusion?



Do you need a reg to tell you not to fly into thunderstorms?


Nope. Do you?



Do you need a reg to tell you not to fly into known icing conditions
with an aircraft not approved for it?


Nope do you?



Do as you wish. Just don't take anyone with you should you fall prey
to Darwinism.


Do you see any similarity at all between flying into thunderstorms or flying
into known icing conditions with an aircraft not approved for it and
enroute IFR navigation by handheld GPS in US controlled airspace?

Ron Lee wrote:

I'm left to conclude that you are not a pilot to entrust with anyone's
life. Do you need a reg to tell you not to fly into thunderstorms?
Do you need a reg to tell you not to fly into known icing conditions
with an aircraft not approved for it?

Do as you wish. Just don't take anyone with you should you fall prey
to Darwinism.

Ron Lee

So you now assume that navigating direct with a handheld GPS is
dangerous? Why is that? I can understand why people disagree whether
its "legal" or not, but safety? And pushing RAIM won't convince me.
I've seen almost as many IFR panel mount units give unreliable data or
drop out unexpectedly as I have seen that happen in handhelds. And
just a couple of days ago someone related the story in another thread
regarding his glideslope instrumentation going bad and causing the
autopilot, on a coupled ILS, to reach DH some two miles early. I'd
call that a safety issue.

In article .com,
wrote:

So you now assume that navigating direct with a handheld GPS is
dangerous? Why is that? I can understand why people disagree whether
its "legal" or not, but safety? And pushing RAIM won't convince me.

If you don't understand RAIM, then why bother asking about safety?

--
Bob Noel
Looking for a sig the
lawyers will hate

Bob Noel wrote:
If you don't understand RAIM, then why bother asking about safety?

I didn't say I didn't understand RAIM. I just don't care. I am not
convinced that it is necessary for enroute navigation that can be
"safely" accomplished with 30-year old VOR receivers.

My question is how is using a handheld GPS while in radar contact
unsafe? Or more to the point, how is it less safe than using a
combination of radar vectors and VORs? Is "fly heading 320, direct XYZ
VOR when able" any safer?

Sure a panel-mount TSOed IFR approved GPS is supposed to tell you when
its got an inconsistent solution of your position, and therefore it is
more reliable than a handheld, but we're not comparing panel mounts
with handhelds. We're comparing ADF/VOR navigation with handheld GPS.

Peter

"Bob Noel" wrote in message
...

If you don't understand RAIM, then why bother asking about safety?


Nothing in his message suggested he doesn't understand RAIM.

wrote:

So you now assume that navigating direct with a handheld GPS is
dangerous? Why is that? I can understand why people disagree whether
its "legal" or not, but safety? And pushing RAIM won't convince me.
I've seen almost as many IFR panel mount units give unreliable data or
drop out unexpectedly as I have seen that happen in handhelds. And
just a couple of days ago someone related the story in another thread
regarding his glideslope instrumentation going bad and causing the
autopilot, on a coupled ILS, to reach DH some two miles early. I'd
call that a safety issue.


When you bring up the ILS G/S you are taking on precision vertical
navigation, which is a different issue.

"Light Tin" approach couplers and ILS G/S installations have been an
issue for as long as I have been flying.

So, just because someone couldn't manage marginal couplers or G/S
receivers/antenna installations is really not relevant to use of
handhelds for IFR.

And, here the issue in the thread has primarily been legal, not safety.

I have argued with Ron before that, given reasonable, personal integrety
checks, I would be safer flying a VOR overlay approach with my Garmin
296 than with a light tin VOR receiver.