Implications of.....keeping the speed up

So let's say I'm inbound to Teterboro from the west, doing 250 kias
below 10,000 in descent. Atc gives me a radar vector, and clears me
to maintain 4000 feet.

1, Do I need to slow to 200 kias at some time?

2. I'm considering that I may well be less than 3000 feet AGL (or is
2500 the magic number?). Does this have any bearing?

3. Do I need to worry about being underneath a class B, and thus have
a 200 kias speed limit? Or does atc somehow take care of this for me.

Thanks for all inputs. Stan

On 01/04/07 13:40, wrote:
So let's say I'm inbound to Teterboro from the west, doing 250 kias
below 10,000 in descent. Atc gives me a radar vector, and clears me
to maintain 4000 feet.

1, Do I need to slow to 200 kias at some time?

2. I'm considering that I may well be less than 3000 feet AGL (or is
2500 the magic number?). Does this have any bearing?

3. Do I need to worry about being underneath a class B, and thus have
a 200 kias speed limit? Or does atc somehow take care of this for me.

Thanks for all inputs. Stan


The FARs spell out the speed limits. Are you asking what they say, or
are you asking if you can violate the FARs if ATC asks you to maintain
your speed?

In article ,
wrote:

So let's say I'm inbound to Teterboro from the west, doing 250 kias
below 10,000 in descent. Atc gives me a radar vector, and clears me
to maintain 4000 feet.

1, Do I need to slow to 200 kias at some time?

Almost certainly, yes, at some point prior to when you flare :-)

I suspect you're thinking of the restrictions imposed by 14 CFR 91.117. It
imposes three basic speed limits:

A) 250 KIAS below 10,000 MSL

B) 200 KIAS below 2500 AGL or within 4 NM of a Class C or D airport.

C) 200 KIAS beneath Class B airspace.

A requires the administrator to waive. B requires ATC to waive. C is
non-waivable. Minimum safe airspeed trumps all those. That's usually only
a factor for a heavy jet right after takeoff.

In your case, B is probably what applies. If you want to exceed 20 KIAS,
make a request of the controller.

On Thu, 04 Jan 2007 18:57:19 -0500, Roy Smith wrote:

If you want to exceed 20 KIAS,
make a request of the controller.

Generally in the form of "Request takeoff, departure to..."

Thanks Roy. I don't have a US licence, so hence my questions. My
thoughts we

200 below class B. So will atc vector me below class B, possibly? In
which case, do pilots normally have a class B airspace chart out, tune
in the EWR VOR, and carefully monitor radials, dme's, altitudes, in
order to slow to 200 prior to being under class B? Somehow, I don't
think most actually do this.

250 below 2500 agl within 4 nm of C or D. Again, does anyone monitor
a low level chart and crosscheck their radial/dme with local vor's in
order to ascertain whether they meet this criteria? Again, I think
most of us are starting to tune in the localizer at this point.

Secondly, if this is reference the elevation of the primary airport,
who really continuously looks up airport elevations as they go (and
airports may be 3 or 4000 msl west of Teb in the appalachians I
presume) adds 2500, and ensures they are above this altitude.
Further, if I'm descended early into TEB, as expected for an arrival
into the NE, and am at 6000 msl 60 miles to the west, is atc really
expecting a sudden decrease to 200 this far out? Somehow I'd expect a

"CFxxx say speed, ...and this aint Dallas so pick it back up to 250
please"

So I guess I'm asking, what would you use in a situation like this to
decide when to slow to 200?

..On Thu, 04 Jan 2007 18:57:19 -0500, Roy Smith wrote:

In article ,
wrote:

So let's say I'm inbound to Teterboro from the west, doing 250 kias
below 10,000 in descent. Atc gives me a radar vector, and clears me
to maintain 4000 feet.

1, Do I need to slow to 200 kias at some time?

Almost certainly, yes, at some point prior to when you flare :-)

I suspect you're thinking of the restrictions imposed by 14 CFR 91.117. It
imposes three basic speed limits:

A) 250 KIAS below 10,000 MSL

B) 200 KIAS below 2500 AGL or within 4 NM of a Class C or D airport.

C) 200 KIAS beneath Class B airspace.

A requires the administrator to waive. B requires ATC to waive. C is
non-waivable. Minimum safe airspeed trumps all those. That's usually only
a factor for a heavy jet right after takeoff.

In your case, B is probably what applies. If you want to exceed 20 KIAS,
make a request of the controller.

writes:

In which case, do pilots normally have a class B airspace chart out, tune
in the EWR VOR, and carefully monitor radials, dme's, altitudes, in
order to slow to 200 prior to being under class B? Somehow, I don't
think most actually do this.

If you have RNAV capability and moving maps (like a GPS unit), you
don't need to, since your instruments will show you the controlled
airspaces and tell you if you are within them. If you don't have
that, you might or might not have time to check in real time, but you
certainly need to know whether or not you're in Class B, for example.
You can also plan your flight in advance and check all of these
details so that you will know where you are at all times without
having to check charts in flight. If you have no idea at all how
close you are to controlled airspace, you need to work on your
navigation and planning skills before you go anywhere near airports of
significant size.

250 below 2500 agl within 4 nm of C or D. Again, does anyone monitor
a low level chart and crosscheck their radial/dme with local vor's in
order to ascertain whether they meet this criteria? Again, I think
most of us are starting to tune in the localizer at this point.

You might well be flying below that altitude in some cases without
necessarily being on an approach for landing, albeit probably not in a
757.

Also, if you're preparing to intercept a localizer, you're already
slowing down considerably, and in many cases below 200 kts. Even
heavy jet aircraft can stay below 200 kts with flaps.

Secondly, if this is reference the elevation of the primary airport,
who really continuously looks up airport elevations as they go (and
airports may be 3 or 4000 msl west of Teb in the appalachians I
presume) adds 2500, and ensures they are above this altitude.

It's above the ground below you. And some areas are quite flat. And
you may have a radar altimeter that lets you know how far you are
above the ground. If you are VFR, you may be able to judge your
altitude well enough by visual means alone.

Further, if I'm descended early into TEB, as expected for an arrival
into the NE, and am at 6000 msl 60 miles to the west, is atc really
expecting a sudden decrease to 200 this far out?

Why would it be sudden? If it comes as a surprise to you while you
are flying along, there's something wrong. And if you are flying below
2500 AGL, you're probably either in the military or you have a small
plane that can't do much better than 200 kts, anyway. If you are
below Class B, you're pretty close to a major airport (much closer
than 60 nm). Also, since Class B normally extends only to 10,000, the
space below it is rarely more than a few thousand feet high, so you're
no more likely to be below it than you are to be at 2500 AGL. Unless
you're in a small plane that flies at these altitudes normally, of
course.

So I guess I'm asking, what would you use in a situation like this to
decide when to slow to 200?

Your position and altitude, which you should always know with a fair
degree of accuracy.

--
Transpose mxsmanic and gmail to reach me by e-mail.

Just to clarify, I have no moving map, so no depiction of class D C B.
Hence my inquiry on whether it's normal for pilots to have out class
B and low level charts. To clarify, this was flown in hi airspace,
and yes we had our hi enroute out, but it is of little help.

Re check in real time:
I presume you mean as I said by tuning in the ewr vor and monitoring
radials and dme.

Re plan in advance, it's just not always possible. This was a quick
trip, filed from Southern Ontario Canada, no prefered route available,
and the one we chose to file was from CYYZ. No surprise, we didn't
get the route we expected, with CLE centre re routing/vectoring us
enroute. then via vectors (NY) for the arrival. So.... descending 60
west of TEB at 6000 feet at 250 kias, did I break the max 200 kias
within 4 nm and 2500 AGL? I've no idea, perhaps. Hence my inquiry on
how others handle this situation.

Re not knowing how close I am to controlled airspace:
I'd think this is mostly class E airspace I'm in, and is controlled,
isn't it? And I know exactly where I am; I'm 59 dme from the TEB dme,
on the 275 radial. And I'm just setting up my fms for the ils 06 Teb,
so I know the XYZ IF is bearing ABC degress for DEF miles. I just
don't know the distance before I enter the EWR class B airspace. And
nor do I know whether in fact, due to altitude changes, I may end up
under it. Note I'm not saying I can't find out, I just didn't have a
low chart out at this point.

See a few comments further below

If you have RNAV capability and moving maps (like a GPS unit), you
don't need to, since your instruments will show you the controlled
airspaces and tell you if you are within them. If you don't have
that, you might or might not have time to check in real time,
You can also plan your flight in advance and check all of these
details so that you will know where you are at all times without
having to check charts in flight. If you have no idea at all how
close you are to controlled airspace, you need to work on your
navigation and planning skills before you go anywhere near airports of
significant size.


Secondly, if this is reference the elevation of the primary airport,
who really continuously looks up airport elevations as they go (and
airports may be 3 or 4000 msl west of Teb in the appalachians I
presume) adds 2500, and ensures they are above this altitude.

It's above the ground below you. And some areas are quite flat. And
you may have a radar altimeter that lets you know how far you are
above the ground. If you are VFR, you may be able to judge your
altitude well enough by visual means alone.

West of Teb is not that flat. And my altimeter comes alive at 2000
agl. And often IMC.

Further, if I'm descended early into TEB, as expected for an arrival
into the NE, and am at 6000 msl 60 miles to the west, is atc really
expecting a sudden decrease to 200 this far out?

Why would it be sudden? If it comes as a surprise to you while you
are flying along, there's something wrong. And if you are flying below
2500 AGL, you're probably either in the military or you have a small
plane that can't do much better than 200 kts, anyway.

It's not a surprise to me, and perhaps sudden is too harsh a word.
Typically I descend below 10000 at 250 kias. When I want to slow to
200, if possible I aim to pull throttles to idle, and decrease the
descent rate. I'm thinking that since atc is vectoring me, the
planned separation from other aircraft may be reduced by my perhaps
unanticipated speed reduction that far out. Just a thought.

Well thanks for your inputs. I found them useful. I am 100% sure
that corporate pilots do NOT have low level charts out, nor Class B
charts on these trips. I gather from here that in order to ensure
these speed limits are followed, one needs both, plus perhaps a
sectional for the 2500 AGL limitation.

Thanks to Roy too for his response.
Stan

plus perhaps a
sectional for the 2500 AGL limitation.

It's good to have sectionals available (or at least WACs) but 2500 AGL
should be pretty easy to eyeball.

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

"Roy Smith" wrote in message
...

B) 200 KIAS below 2500 AGL or within 4 NM of a Class C or D airport.


Slight correction...... delete the word "or".

wrote:
So let's say I'm inbound to Teterboro from the west, doing 250 kias
below 10,000 in descent. Atc gives me a radar vector, and clears me
to maintain 4000 feet.

1, Do I need to slow to 200 kias at some time?

2. I'm considering that I may well be less than 3000 feet AGL (or is
2500 the magic number?). Does this have any bearing?

3. Do I need to worry about being underneath a class B, and thus have
a 200 kias speed limit? Or does atc somehow take care of this for me.

Does it seem odd that a guy flying something doing 250 knots is asking
about basic FARs?
-Robert