FAR Part 97: Aircraft Approach Categories - IAS vs Ground Speed

On 7/15/2005 11:12, Michael wrote:

According to 14 CFR Part 97.3 (b), it provides the speed ranges for
the different aircraft categories (A-E). In all the documentation I've
read, this "speed" is the IAS of the airplane.

And so it is (almost - I seem to recall it's really CAS, but that
wouldn't make much difference). That's the regulation.

However, my CFI says that this is based on the Ground Speed.

It's hard to prove a negative, so I can't say there is NO regulatory
support for what he says, but I've certainly never seen it. Have you
asked him to show you where he read this? Further, without RNAV that
works at low altitudes or DME on the approach (which isn't rare but is
far from universal), ground speed is an estimate - and these rules are
a lot older than widespread use of RNAV that works at low altitudes.

In other words - I think your CFI is totally wrong on this one.

The reason I ask is that I've been asked questions before where the
examiner was trying to make sure that I completely understood the
rule, and I'm worried that selecting minimums that are higher than
necessary will show that I don't really understand it.

Well, yes, it will. Only I think you understand it fine; it's your
instructor who is steering you wrong.

There are situations where it makes sense to select higher minimums on
an approach (especially a circling approach) where the higher speed
makes remaining within the protected area for the lower mins
problematic. I certainly don't think it would be wrong to say "Yes, I
know that technically cat A mins apply, but I am going to use Cat B
mins because the wind conditions make remaining within the Cat A
protected area problematic." If the situation is a circling approach
with restrictions imposed and very high winds that would require an
excessive bank angle to remain within the protected area, he would
probably consider that a sign of good judgment. But you should be
clear that this is something you are choosing to do because it makes
sense, and that the regulations do permit lower mins.

Thank you Michael. This is how I've been looking at it (but I didn't
express it very well).

When I've asked my CFI to show me the regs, he basically says that it
makes sense to use the higher mins, and I haven't pushed it. This isn't
the first time we've disagreed on the Regs. In another case, he claimed
that it was illegal to fly IFR without a flight plan and ATC clearance,
but that rule applies only to Controlled airspace.

I think I won't bother pushing it, as I'm clear on the concept, and
don't really need to head-but the CFI over it ;-)


Michael



--
Mark Hansen, PP-ASEL, Instrument Student
Sacramento, CA

"Mark Hansen" wrote in message
...
On 7/15/2005 11:12, Michael wrote:

According to 14 CFR Part 97.3 (b), it provides the speed ranges for
the different aircraft categories (A-E). In all the documentation I've
read, this "speed" is the IAS of the airplane.

And so it is (almost - I seem to recall it's really CAS, but that
wouldn't make much difference). That's the regulation.

However, my CFI says that this is based on the Ground Speed.

It's hard to prove a negative, so I can't say there is NO regulatory
support for what he says, but I've certainly never seen it. Have you
asked him to show you where he read this? Further, without RNAV that
works at low altitudes or DME on the approach (which isn't rare but is
far from universal), ground speed is an estimate - and these rules are
a lot older than widespread use of RNAV that works at low altitudes.

In other words - I think your CFI is totally wrong on this one.

The reason I ask is that I've been asked questions before where the
examiner was trying to make sure that I completely understood the
rule, and I'm worried that selecting minimums that are higher than
necessary will show that I don't really understand it.

Well, yes, it will. Only I think you understand it fine; it's your
instructor who is steering you wrong.

There are situations where it makes sense to select higher minimums on
an approach (especially a circling approach) where the higher speed
makes remaining within the protected area for the lower mins
problematic. I certainly don't think it would be wrong to say "Yes, I
know that technically cat A mins apply, but I am going to use Cat B
mins because the wind conditions make remaining within the Cat A
protected area problematic." If the situation is a circling approach
with restrictions imposed and very high winds that would require an
excessive bank angle to remain within the protected area, he would
probably consider that a sign of good judgment. But you should be
clear that this is something you are choosing to do because it makes
sense, and that the regulations do permit lower mins.

Thank you Michael. This is how I've been looking at it (but I didn't
express it very well).

When I've asked my CFI to show me the regs, he basically says that it
makes sense to use the higher mins, and I haven't pushed it. This isn't
the first time we've disagreed on the Regs. In another case, he claimed
that it was illegal to fly IFR without a flight plan and ATC clearance,
but that rule applies only to Controlled airspace.

I think I won't bother pushing it, as I'm clear on the concept, and
don't really need to head-but the CFI over it ;-)


Michael



--
Mark Hansen, PP-ASEL, Instrument Student
Sacramento, CA

I would fire him when it is convienent. There is no point in using a CFII
that not only harbors errors in his understanding but is also incapable of
learning and changing his position when it is pointed out to him. Of
course, that applies to all people and all fields.

Mike
MU-2

"Mark Hansen" wrote in message
...
When I've asked my CFI to show me the regs, he basically says that it
makes sense to use the higher mins, and I haven't pushed it.

But using ground speed instead of airspeed could result in selecting lower
mins rather than higher.

--Gary

On 7/15/2005 12:57, Gary Drescher wrote:

"Mark Hansen" wrote in message
...
When I've asked my CFI to show me the regs, he basically says that it
makes sense to use the higher mins, and I haven't pushed it.

But using ground speed instead of airspeed could result in selecting lower
mins rather than higher.

That's right. I don't know what he thinks about this case.


--Gary




--
Mark Hansen, PP-ASEL, Instrument Student
Sacramento, CA

"Gary Drescher" wrote in message
...

But using ground speed instead of airspeed could result in selecting lower
mins rather than higher.


And it will in most cases, as most approaches are flown into the wind.

Mark Hansen wrote in
:

In another case, he claimed
that it was illegal to fly IFR without a flight plan and ATC clearance,
but that rule applies only to Controlled airspace.

Well, it can be illegal. My ops manual forbids it, so it's illegal for
me. My ops manual obviously doesn't apply to you, though, nor any other
aircraft not covered by it. That's just a small nit, though. If I were
you, I would be seriously considering finding a new CFII, one who
actually knows something about flying IFR. All too often, it's the blind
leading the blind.

--
Regards,

Stan

"They that can give up essential liberty to obtain a little temporary
safety deserve neither liberty nor safety." B. Franklin

"Stan Gosnell" wrote in message
...
If I were
you, I would be seriously considering finding a new CFII, one who
actually knows something about flying IFR.

I don't dispute that it's worth considering; still, I think it's possible
that the CFII is a good one. His interpretation of some regs may be sketchy,
but not in a way that adversely affects safety. No pilot should ever take a
CFI's word for what the regs say anyway, so a responsible pilot (as Mark
gives every indication of being) won't be misled by a CFI's
misinterpretation of the regs.

--Gary

On 7/15/2005 15:15, Gary Drescher wrote:

"Stan Gosnell" wrote in message
...
If I were
you, I would be seriously considering finding a new CFII, one who
actually knows something about flying IFR.

I don't dispute that it's worth considering; still, I think it's possible
that the CFII is a good one. His interpretation of some regs may be sketchy,
but not in a way that adversely affects safety. No pilot should ever take a
CFI's word for what the regs say anyway, so a responsible pilot (as Mark
gives every indication of being) won't be misled by a CFI's
misinterpretation of the regs.

Thanks for that, Gary.

As a matter of fact, I think he is a good CFI. He knows how to use the
IFR system, he knows how to work with ATC, etc. He's been able to answer
all my questions and doesn't bull**** me, which I really like.

When we have disagreements (which are few), he doesn't get all puffed
up about it, which makes it possible for us to "discuss" it thoroughly.

All in all, I think the discussions that are generated by these
disagreements are better for me in the long run (perhaps for him
as well), so I don't mind them at all.

Besides, the CFI is only part of the resources I have available for
my training. When he suggests something that I think doesn't line-up
with what I've learned/read elsewhere, we talk about it.

I'm quite pleased with his performance. He has a genuine desire to
teach, and that make a real big difference, in my opinion.


--Gary




--
Mark Hansen, PP-ASEL, Instrument Student
Sacramento, CA

For that matter, don't accept what the FAA says about the regs, unless it
comes from the regulatory support division. The folks at FSDO know even
less about the FARs than the uninformed CFIs.



"Gary Drescher" wrote in
news
"Stan Gosnell" wrote in message
...
If I were
you, I would be seriously considering finding a new CFII, one who
actually knows something about flying IFR.

I don't dispute that it's worth considering; still, I think it's
possible that the CFII is a good one. His interpretation of some regs
may be sketchy, but not in a way that adversely affects safety. No
pilot should ever take a CFI's word for what the regs say anyway, so a
responsible pilot (as Mark gives every indication of being) won't be
misled by a CFI's misinterpretation of the regs.

--Gary