200 kts relief

But I think that on the arrival in question, you're descending from the flight levels (at 29.92) and as you pass out of the class A airspace you may find yourself at a significantly different altitude than you expected depending on pressure (after you change the altimeter setting), and you might end up busting an altitude restriction.

Isn't that why you are supposed to change to a local altimeter setting passing through the transition level?
 
I thought the issue was that pilots were following the glideslope thinking that since they were already cleared for the approach, they didn't have to worry about the stepdowns. The problem wasn't possibly running into something, but that the vertical airspace limits are defined in terms of barometric altitudes.

I think you're right! I'm confused.
 
Isn't that why you are supposed to change to a local altimeter setting passing through the transition level?

Yes, it is. I think Liz has the right issue where folks were following the glideslope outside the FAF and were ignoring the stepdown limits.

I'm thinking of a case where there was something like a 17000 floor on a star and aircraft who were descending at a good rate weren't switching the altimeter setting in time and when they levelled off at 17000 at 2992 they were low enough to set off the snitch. It's not an issue for a crew that's thinking ahead, but I believe it has hit some single-pilot jets.
 
Well, since the boundaries of any airspace contract and expand with pressure and temperature too I suppose it's possible that the airspace itself could expand on a hot high-pressure day and leave a fixed thing like a glide slope outside.

Haven't heard of it but sounds plausible. Should be fixed by simply redrawing airspace and lowering floors and such to include hot / high days.
 
Well, since the boundaries of any airspace contract and expand with pressure and temperature too I suppose it's possible that the airspace itself could expand on a hot high-pressure day and leave a fixed thing like a glide slope outside.

Haven't heard of it but sounds plausible. Should be fixed by simply redrawing airspace and lowering floors and such to include hot / high days.
So solve the problem by reducing the airspace available to us bugsmashers around major metropolitan areas? Can't say I'm real enamored of that idea, either!
 
So solve the problem by reducing the airspace available to us bugsmashers around major metropolitan areas? Can't say I'm real enamored of that idea, either!

Would you rather fly into the guy on the approach?

5 miles out on the GS is a fixed point in space. The protected airspace 'floats' up and down due to pressure and temp. If that airspace is G during day then that 1 mile clear of clouds might not provide the protection that's required.
 
Would you rather fly into the guy on the approach?

5 miles out on the GS is a fixed point in space. The protected airspace 'floats' up and down due to pressure and temp. If that airspace is G during day then that 1 mile clear of clouds might not provide the protection that's required.
But 5 miles out on the GS is going to be within the area of the Bravo that goes to the ground in every case I'm aware of, so the airspace has already been reserved, no matter what the pressure and temp. So it seems that we must be talking something further out.
 
Yeah, I don't know the approach in question. I'd imagine it's not bravo we're talking about unless it's a weird one with a cutout. I'm just saying how it 'could' happen on a hot high pressure day...like what might be seen in Cali.
 
Yeah, I don't know the approach in question. I'd imagine it's not bravo we're talking about unless it's a weird one with a cutout. I'm just saying how it 'could' happen on a hot high pressure day...like what might be seen in Cali.
I guess I was thinking about approaches to class B airports. I would expect that going into the non-primary airport they would tend to vector you around the class B as much as possible, so you're not going to be gaining much (and likely losing some) by expanding the class B. Just conjecture, though.
 
So solve the problem by reducing the airspace available to us bugsmashers around major metropolitan areas? Can't say I'm real enamored of that idea, either!

It only reduces our flying area in places where controllers won't let us in. Not the norm, everywhere.

I've had at least an 80% success rate getting cleared into the Denver Bravo VFR, but with the IR I probably won't have to bother with it much anymore, so my statistics will be rather sparse from now on. ;)

I'm 1 for 1 getting into the LAS Bravo, but boy they wanted me out ASAP. ;)
 
I thought the issue was that pilots were following the glideslope thinking that since they were already cleared for the approach, they didn't have to worry about the stepdowns. The problem wasn't possibly running into something, but that the vertical airspace limits are defined in terms of barometric altitudes.

This happened at LAX on the 25L/R or 24L/R ILSes on more than one very hot summer days than I can remember. The air mass rose sufficently that being on the ILS G/S caused the pilots to bust the 1,000 feet of required vertical separation over the Ontario sector below. The true altitude of the G/S remained unchanged, but the Ontario sectors airspace rose with the high temperature. Had the crews instead adhere to the stepdown fixes they would have been above the G/S but within the airspace "owned" by the Los Angeles division of SoCal TRACON.

In most cases they were cleared for the approach, which only means they can descend while obeying the stepdown fixes until at the point where the G/S becomes primary (usually the P-FAF).

The FAA did rework the stepdown fixes to make this less likely after a slew of violations and enforcement actions. Nonetheless, the principles remain unchanged.

Someone may ask, why was the FAA so hard over on enforcement actions in these cases? Well, LAX bound pilots busted the underlying Ontario airspace all day long on those hot summer days. There had to be a loss of vertical separation, however for an enforcement action to occur; i.e. the computer snitch sounded the alarm to the Ontario controller because he had an IFR aircraft in the area that ate up the three mile lateral (radius) airspace "bubble." In those cases, if the controller doesn't report it then it is a ding on his performance.
 
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It only reduces our flying area in places where controllers won't let us in. Not the norm, everywhere.

I've had at least an 80% success rate getting cleared into the Denver Bravo VFR, but with the IR I probably won't have to bother with it much anymore, so my statistics will be rather sparse from now on. ;)

I'm 1 for 1 getting into the LAS Bravo, but boy they wanted me out ASAP. ;)

At MSP they keep even IFR GA clear of all Bravo. Seems to be reserved exclusively for the big boys.
 
Would you rather fly into the guy on the approach?

5 miles out on the GS is a fixed point in space. The protected airspace 'floats' up and down due to pressure and temp. If that airspace is G during day then that 1 mile clear of clouds might not provide the protection that's required.
No, I'd rather not fly into the cell tower that is at 1800 msl.

Dude, you gotta share the space and be smart. You're just asking for an airspace grab, and you're not going to get support here....
 
At MSP they keep even IFR GA clear of all Bravo. Seems to be reserved exclusively for the big boys.
I've been in the MSP Bravo on an IFR clearance on many occasions. VFR for that matter too. What they do is keep you away from the arrival and departure corridors.
 
Can you point me to one of those?


oops, I mis-spoke. It's the LNAV/VNAV portion of the approach that has the temperature restrictions.

Take RNAV 16 in KPWK:

For uncompensated Baro-VNAV systems, LNAV/VNAV not authorized below -16C (4F) or above 39C (102F).

Maybe LPV requires a compensated Baro so that's why it's not an issue? Anyway, the point is airspace rises and falls with temperature and pressure. We compensate in the cockpit for pressure but not for temperature.
 
oops, I mis-spoke. It's the LNAV/VNAV portion of the approach that has the temperature restrictions.

Take RNAV 16 in KPWK:



Maybe LPV requires a compensated Baro so that's why it's not an issue? Anyway, the point is airspace rises and falls with temperature and pressure. We compensate in the cockpit for pressure but not for temperature.

Baro VNAV is not required for LPV. Nor is there any temperature compenstation once the LPV P-FAF is the active waypoint. Prior to that any stepdown fixes have the same problem as ILS stepdown fixes; e.g., your're suppose to adhere to the stepdown fixes in those earlier phases of the IAP. LPV = ILS except LPV is always stable unlike many ILSes.

As to LNAV/VNAV the temp limit does not apply passing the P-FAF with a WAASderived vertical path.
 
If you're on a WAAS derived vertical path wouldn't you just be on the LPV?

I do apologize for saying "LPV" before when I should have said "LNAV/VNAV". Honest mistake...really.
 
Had a thought about the 200 kts thing...

How about this?: The rule is changed so that IFR acft with a working TCAS are exempt from the rule. Any time a waiver is issued for an acft to operate in the Class B without a transponder then all acft have to comply with the 200 kts speed restriction. Coupled with this ATC is required to advise all IFR traffic when a vector/descent will take that acft below the Class B.


Basically I'm saying the same thing but adding that if a xponder waiver is issued then the new rule is void for that Class B airspace.
 
If you're on a WAAS derived vertical path wouldn't you just be on the LPV?

I do apologize for saying "LPV" before when I should have said "LNAV/VNAV". Honest mistake...really.

Only if the chart has an LPV line of minimums. Some charts have LNAV/VNAV but not LPV. So, with a WAAS navigator the VNAV path would be WAAS derived and the charted temperature limit does not apply.
 
Only if the chart has an LPV line of minimums. Some charts have LNAV/VNAV but not LPV. So, with a WAAS navigator the VNAV path would be WAAS derived and the charted temperature limit does not apply.

Good point.
 
Had a thought about the 200 kts thing...

How about this?: The rule is changed so that IFR acft with a working TCAS are exempt from the rule. Any time a waiver is issued for an acft to operate in the Class B without a transponder then all acft have to comply with the 200 kts speed restriction. Coupled with this ATC is required to advise all IFR traffic when a vector/descent will take that acft below the Class B.


Basically I'm saying the same thing but adding that if a xponder waiver is issued then the new rule is void for that Class B airspace.

1. Why does it matter whether the aircraft is IFR or VFR?

2. How does the transponder in the Class B waiver provision mitigate the issue with non-transponder aircraft outside of the Class B?
 
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1. Because most cockpits in Class B under IFR rules don't have sectionals to depict the altitudes or GPS displays capable of depicting the airspace. Plus, by definition IFR is talking to ATC so why not let ATC control the speed?

2. I do not understand the question. The topic is airspeed under the Bravo and ALL of that area is covered by the Mode C veil. Aircraft operating without a transponder outside the veil are outside the topic.
 
1. Because most cockpits in Class B under IFR rules don't have sectionals to depict the altitudes or GPS displays capable of depicting the airspace. Plus, by definition IFR is talking to ATC so why not let ATC control the speed?

2. I do not understand the question. The topic is airspeed under the Bravo and ALL of that area is covered by the Mode C veil. Aircraft operating without a transponder outside the veil are outside the topic.

Let's take these in reverse order. I didn't say anything about operations outside the Mode C veil. Your proposal specifies non-transponder aircraft waivered to operate in the Class B airspace.
How about this?: The rule is changed so that IFR acft with a working TCAS are exempt from the rule. Any time a waiver is issued for an acft to operate in the Class B without a transponder then all acft have to comply with the 200 kts speed restriction.
It doesn't address potential conflicts with non-transponder equipped aircraft that can operate outside the Class B, but inside the Mode C veil IAW 91.215(b)(3).

As for IFR vs. VFR, any successful proposal will have to mitigate the hazard the current regulation was enacted to deal with, in this case the ability to see and avoid the congestion of VFR aircraft just outside of Class B airspace. This is Class E airspace where see and avoid is the rule. Since controllers aren't responsible for separating IFR from VFR traffic in the airspace, why would they be the ones to decide what speed you can fly.
 
Since you changed the order;

1 (old 2). Guess that's a problem. Don't know. Get rid of 91.215 b(3)?

2 (old 1). A pilot should be able to know what airspace they are in. Right now most Class B pilots do not. If they don't have the means to know where the floor of the Bravo is then they don't know when that descent took them through it. If they don't know when they go through it they get nervous when approach says, "say speed". If they say 250 kts then a violation and a short career may be looking at them. My feeling is that is not fair or right.
 
Since you changed the order;

1 (old 2). Guess that's a problem. Don't know. Get rid of 91.215 b(3)?

2 (old 1). A pilot should be able to know what airspace they are in. Right now most Class B pilots do not. If they don't have the means to know where the floor of the Bravo is then they don't know when that descent took them through it. If they don't know when they go through it they get nervous when approach says, "say speed". If they say 250 kts then a violation and a short career may be looking at them. My feeling is that is not fair or right.
Jepps have very nice terminal charts. You have 'em, it's just another da_ned task in the approach to look at 'em.
 
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Well, you are correct, Jepps has this;

photo.PNG



I suppose it would be good to use to familiarize yourself going in. You could guess based on the direction you are arriving from. But I'm not sure how practical it would be to use for actually knowing where you are on it and determining if you are in or below the Class B. Does it even have a scale that could be used to plot your location?

Imagine you take off to the South. You clean up the plane and start getting vectored to the East. The floor there is 3,000 and you are level at 4,000. They turn you towards the North and give you a 020 heading level at 4,000. At some point you may fly across the line and get into the area where the floor is 6,000.

How would you know? The second you cross that line you are in violation of the FARs and that's my point of this entire thread...with this chart you just don't know. And I don't think it's fair that guys and gals get violated over this.
 
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At MSP they keep even IFR GA clear of all Bravo. Seems to be reserved exclusively for the big boys.

It depends. At some, they keep you clear of arrival/departure corridors but let you through other times (even the IAD airspace). But most transit traffic will be sent around. CVG is better now, used to be you went around regardless (got a snotty lecture from a controller one day when I made a request to transit on IFR). Chicago - go around. NYC, usually transit - they'll take you right over JFK. Others: it depends.

STL tried to send me around one clear day - my solution was to cancel and go over the top. We negotiated a transit route. :yes:
 
I haven't gone through all 5 pages of the replies on this, but after a few, why not put something in your flight plan, maybe a user fix to tell you before you get to the class B?
 
Well, you are correct, Jepps has this;

photo.PNG



I suppose it would be good to use to familiarize yourself going in. You could guess based on the direction you are arriving from. But I'm not sure how practical it would be to use for actually knowing where you are on it and determining if you are in or below the Class B. Does it even have a scale that could be used to plot your location?

Imagine you take off to the South. You clean up the plane and start getting vectored to the East. The floor there is 3,000 and you are level at 4,000. They turn you towards the North and give you a 020 heading level at 4,000. At some point you may fly across the line and get into the area where the floor is 6,000.

How would you know? The second you cross that line you are in violation of the FARs and that's my point of this entire thread...with this chart you just don't know. And I don't think it's fair that guys and gals get violated over this.

With that chart and the G-1000 moving map you've got it all.
 
I haven't gone through all 5 pages of the replies on this, but after a few, why not put something in your flight plan, maybe a user fix to tell you before you get to the class B?

The problem is that in most Class B exit/re-enter scenarios, you don't know in advance where you are going to be sent out and under the class B. It is situational. The main reason is that traffic exceeds the capacity of the class B design and can't be contained in the class B at peak times. The primary example is where you are in a line on downwind that extends beyond the protection of the class B, and all traffic in the line exits at the far end of the downwind leg and reenters the class B on final. The class B should contain all of the traffic, but when it doesn't, traffic is forced to exit. The controllers have to use a uniform speed or they will cause compression on the downwind. IMHO, the best solution is to make the class B do the job it was intended to do, separate high performance aircraft from lower performance aircraft and when it can't, slow all the traffic down to less than 200 Kts.
 
The problem is that in most Class B exit/re-enter scenarios, you don't know in advance where you are going to be sent out and under the class B. It is situational. The main reason is that traffic exceeds the capacity of the class B design and can't be contained in the class B at peak times. The primary example is where you are in a line on downwind that extends beyond the protection of the class B, and all traffic in the line exits at the far end of the downwind leg and reenters the class B on final. The class B should contain all of the traffic, but when it doesn't, traffic is forced to exit. The controllers have to use a uniform speed or they will cause compression on the downwind. IMHO, the best solution is to make the class B do the job it was intended to do, separate high performance aircraft from lower performance aircraft and when it can't, slow all the traffic down to less than 200 Kts.

I don't know. Say the final approach controller needs to send just one guy out to fill a gap. The entire class B needs to slow to 200kts? That seems extreme. I say just tell the guy who is getting vectored out.

"Citation123, exiting the Bravo, slow to 200, heading 180."

"Roger, slowing to 200 heading 180, Citation 123".
 
I don't know. Say the final approach controller needs to send just one guy out to fill a gap. The entire class B needs to slow to 200kts? That seems extreme. I say just tell the guy who is getting vectored out.

"Citation123, exiting the Bravo, slow to 200, heading 180."

"Roger, slowing to 200 heading 180, Citation 123".

ATC is going to match speeds on the downwind so they don't get compression. If one aircraft goes outside the Bravo, a bunch will end up outside the Bravo or they wouldn't have needed to send the first guy out, they would have found a way to contain him.
 
The speed limit isn't only an arrival problem. The LOUPE ONE off of San Jose, CA is kinda sporty in a 737, with the 200kt limit until you're in the SFO class B or beyond its lateral limits. Might still have flaps out through 8000ft.
 
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