Staying in class B on a Vis app

[luv2fly]

Lets start a list of ILS app that the GS will take you out of the bottom of Class B. I am aware that the FAA has changed most, but I think there is still a few out there.

With all the vis going on it would be nice to have a list of places that the stepdowns need to be followed at least for a bit to insure FAR compliance re: staying within the confines of class B

 

[HalinTexas]

Help me here. Where does it say that you have to stay in the confines of a class B? As far as I know, you just have to follow the regs for whatever airspace you're in. You must be thinking of MDW.

 

[set essential]

It's somewhere in Part 91 under operations in Class B airspace.

 

[purduedchi]

I don't believe that just being on the published step downs will ensure staying within Class B airspace. These steps downs are only to ensure obstacle clearance...that's pretty much the only reason they are there. I know for all class B airports we are given a 10-1 page (I think that is that chart #) that depicts the class B airspace altitudes and boundries. It's up to the pilot to know where he/she is. It's almost like departing from an airport underlaying the Class B...200 knots or slowest clean climb speed until the Class B. From what I can recall, then only thing that you would need to change if going below the Class B on a vis app is your speed...so if it's close, then slow to 200. I do know that PHL will let you know when you are departing the Class B(going below) while they are vectoring you for the visual. Maybe they should all do that.

 

[Ralph Wiggums]

Help me here. Where does it say that you have to stay in the confines of a class B? As far as I know, you just have to follow the regs for whatever airspace you're in. You must be thinking of MDW.

At the risk of being flamed, I've never seen this requirement in print, either.

FWIW, I was bored one day in a hotel in LAS when I looked at the ILS 25L approach to see what differences there would be in Class B protection, etc. if one followed the GS vs. the step-downs from PRINO to the runway.

News flash: The instant you leave 8000' inside of PRINO following the step-down profile, you are descending below the floor of the Class B. PRINO is 21 DME from LAS, but the floor of the Class B doesn't drop from 8000' to 6500' until 20 DME, so for 1 NM, you are below the Class B.

If you remain at 8000' after passing PRINO and intercept the GS before descending, you will still descend below the Class B, but it will only be for about the first 40' or so of the descent. Following the GS the rest of the way results in descending below the 6500' floor of the Class B between about 15.5 and 15.0 DME from LAS, after which time you remain in the Class B until touchdown.

So, following the step-downs exactly puts you below the Class B for 1 NM, while following the GS put you below the Class B for less than 0.5 NM.

These were back-of-the-envelope calculations using a 3 degree GS and a TCH of 64', so someone correct me if I'm wrong. But it appears to me that either way you fly this approach, you're gonna leave and reenter the Class B.

 

[The Prussian]

Somewhere I remember reading where clearance for a visual approach to the primary airport for which the Class B airspace is based upon, is not a clearance to descend below the lateral limits of Class B airspace. Visuals to secondary airports (ie. MDW) you will of course drop below Class B confines, in which case you need to observe the speed limits.

 

[rptrain]

91.131(a)(2) Unless otherwise authorized by ATC, each person operating a large turbine engine-powered airplane to or from a primary airport for which a Class B airspace area is designated must operate at or above the designated floors of the Class B airspace area while within the lateral limits of that area.

 

[m80drvr]

It will also be printed in the ops specs for your company under the authorization to conduct visual approaches.

Las Vegas 25L ILS had that problem but I believe that the FAA lowered the floor the B to fix it. I don't really worry about it much though. Just add it to the list of thins the FAA can bust you on if they feel like it. I just stay at the published altitudes.

 

[luv2fly]

It will also be printed in the ops specs for your company under the authorization to conduct visual approaches.

Las Vegas 25L ILS had that problem but I believe that the FAA lowered the floor the B to fix it. I don't really worry about it much though. Just add it to the list of thins the FAA can bust you on if they feel like it. I just stay at the published altitudes.

Exactly what I was talking about, but I think we still have a few approaches that following the GS will take you out of the B if you are following it outside the GS intercept point.

 

[SWA GUY]

Exactly what I was talking about, but I think we still have a few approaches that following the GS will take you out of the B if you are following it outside the GS intercept point.

So fly the GS 1 dot high....

And if the GS takes you out of the Bravo airspace....then the person that designed the ILS is an idiot.

 

[pilotdiscretion]

There are about a dozen airports around the country that have this problem. If memory serves me right ... DTW / SNA / PHL / LAS are on the list. ATL was on the list but the FAA did something crazy to fix the airspace when the new runway opened last year. CLT will be on the list when their new runway opens. I don't know where the plans are to correct their class B.

Changing a class B airspace is a very long process. You have to get through all of the environmental impact regulations then you have to go up against AOPA. These guys fight like wet cats to keep restrictive airspace like a class B from growing.

As several of you mentioned, you gotta stay sharp with the 10-1 charts to keep from getting violated by some disgruntled FAA guy.

 

[luv2fly]

So fly the GS 1 dot high....

And if the GS takes you out of the Bravo airspace....then the person that designed the ILS is an idiot.

I am not asking how to avoid flying below the class B, Duh!

I was just stirring discussion about compiling a list of suspect app/airports. Just for fun and informational purposes.

I agree that the people that designed some of the stuff we fly are idiots. My favorite are two degree heading changes on departures out of PHX. Or those non-prec stepdowns of 100'.

I find it funny that some 10-1 pages show the class B pictorial and it would be impossible to identify using conventional navaids. Most are dme arcs and radials, but some seem to defy those parameters.

 

[Jim Smyth]

It was rumored that back in the day some guys got violated for going below the Class B because they were still doing 250 kts. Its knida funny though. At MDW if your below the floor at O'hare and you slow the controller will ask you why you slowed. Or he will ask you to maintain the 250 kts. YMMV

 

[wscrj]

It was rumored that back in the day some guys got violated for going below the Class B because they were still doing 250 kts. Its knida funny though. At MDW if your below the floor at O'hare and you slow the controller will ask you why you slowed. Or he will ask you to maintain the 250 kts. YMMV

Been there, seen that. However, ATC cannot clear you to violate a FAR.

 

[SWA/FO]

Been there, seen that. However, ATC cannot clear you to violate a FAR.

Yeah, only YOU can choose which FAR to break.

 

[Mach 80]

The Class B airspace thing needs a complete re-do. You have very busy airports such as Midway that are under and not included in Class B and others such as HOU, that aren't any busier that are included.

At airports with Class B, I find myself not doing visuals as much as I otherwise would simply to let the controller worry about keeping me in Class B airspace rather than me.

 

[wscrj]

Yeah, only YOU can choose which FAR to break.

Well yeah, they have to give enough rope to hang yourself with, right?

 

[Nocturnal1]

Interesting thread, although this seems most appropriate for departures rather than arrivals since at most of these airports, approach is pretty directive with speeds. MDW is the first that comes to mind but I've never gone in there without being told what speed to fly. SRQ is interesting when you arrive from the north over/along TPA. When you land south, you go below TPA's Class B and the speeds apply (theoretically). Was bored one late night, the freq. was quiet, so I asked the TPA approach controller about it and after a long pause they said that it hadn't ever been discussed. We brought it up since you're typically at 250 kts. and then get the slam dunk as the last arrival. At ATL when the downwind gets very strung out, the controller will say that you're exiting class B airspace. What does this mean to me? Nada! I'm doin 180 kts or less (directed). Doesn't mean anything w/ wx either since we're IFR.

 

[Jim Smyth]

Been there, seen that. However, ATC cannot clear you to violate a FAR.

YMMV = Your Mileage May Vary

Its all how you play the game!

 

[Motown]

Been there, seen that. However, ATC cannot clear you to violate a FAR.

Isn't that what the "Unless otherwise authorized by ATC" is for?

91.131(a)(2) Unless otherwise authorized by ATC, each person operating a large turbine engine-powered airplane to or from a primary airport for which a Class B airspace area is designated must operate at or above the designated floors of the Class B airspace area while within the lateral limits of that area.
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[wscrj]

Yup, as far as altitude is concerned. The speed restrictions (200 KIAS/Clean Maneuver) cannot be legally exceeded, unless invoking Captain authority/emergency.

§ 91.117 Aircraft speed.

(c) No person may operate an aircraft in the airspace underlying a Class B airspace area designated for an airport or in a VFR corridor designated through such a Class B airspace area, at an indicated airspeed of more than 200 knots (230 mph).

d) If the minimum safe airspeed for any particular operation is greater than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed.

There is no "unless authorized by ATC" caveot for speed.

Dumb rule, no argument here. But with a Fed in the seat....

 

[elcid]

That's something I still haven't figured out. Why do we "dive and drive" at SWA. If you're cleared for the visual and you stay on the GS you'll hit the step downs, give the pax a better ride, and probably save a little gas in my estimation. Why not just set the GSIA and stay on the GS? I've never seen it done like this anywhere else. Not saying it's wrong, but I'm not sure it's right either. I haven't seen an approach where it makes a difference.

 

[Widow's Son]

I'll tell you why. Usually, you can either be on glideslope or 250 but not both, especially at LAS and SJC that often have tailwinds on extended final.

Staying on the glideslope means that you are going to have to dirty up early and slow everybody up behind you. Or, one of your slopers ahead is doing it and now ATC needs you to slow and it is going to put you way high so now you have to S-turn which really screws the guys behind you.

To keep the final moving fast and efficient, you have to stay at the bottom rungs of the approach ladder in order to have a cushion to slow and configure or slow for the pokey ahead of you.

The dive and drive can be done smoothly with minimal perception to the pax. It is a thing of beauty to watch a string of old schoolers drive 250 as long as they can and then dump the gear and start to configure at eight miles or so and hit final approach speed at 1000AGL. Then along comes a sloper who is slowing and configuring at 20 and the next four or five behind him are forced to slow down too and the whole sewer gets backed up.

Like most skills, it is all in the execution. It can be done very smoothly and efficiently.

 

[Saabslime]

There are also several airports where you have to pay attention to class B boundaries and speed on departure. One that comes to mind is San Jose CA right under SFO's airspace. We've had a couple of guys get LOI's by an overzealous Fed while accelerating to 250 after cleanup.

Would it really be that hard to come up with a departure procedure with altitude/speed restrictions in these cases? I know this is basic airmanship but it's just one more landmine out there we have to worry about.