10000 feet procedures and high altitude airports

[NGXfanatic 85]

Hello. I have conducted some simulator sessions at high altitude airports, namely KDEN (Denver, CO) and KJAC (Jackson Hole, WY), where I reach 10,000 feet much more quickly relative to most other U.S. airports. At 10,000 feet, in compliance with FAA regs, I start the acceleration from 250kts to climb speed and turn off the landing lights.

 

I have always wondered what happens in the real world. Do they still perform these tasks at 10,000ft ASL (above sea level), or do they wait until 10,000 AGL (above ground level)? Is the 10,000 ft rule set in stone, regardless of the destination/origin airport elevation? What happens with airports above the 10,000ft mark?

 

Just curious!

[scandinavian13 5,192]

That's a good question. I'll let those who do it weigh in with an official answer, but I'll add my thoughts in the mean time:

 

A lot of the high altitude airports are lesser frequented than a major Class B, which is why you'll see that a lot of those airports are Class D at most (at least in that area). Traffic, of course, depends on the season, and there's even a specific FAA playbook for heavy traffic to those airports (chart makes no symbolic distinction between departure and arrival fields):

 

 

So, despite contradicting myself a little there, my main point is that lighting yourself up is to make you more visible in congested areas. As far as lighting goes, at a less trafficked airport it's not as much of a concern, so cleaning up at 10,000' in order to keep things standard wouldn't be too unreasonable. Then again, as I mentioned, there are periods where traffic to and from those airports can get heavy, which may mean a pilot may want to choose to leave them on until they get higher.

 

I think in the end, it'll probably be answered by the company SOP (which may or may not provide an exception), but always remember that the PIC has operational authority to adjust procedures to maintain a desired margin of safety.

[wims80 121]

Its always 10 000 feet afaik. Imagine youre flying around at 13 000 feet and 280 knots, all of a sudden there's an airport ahead at 4000 feet. You should of course not have to slow down to 250 while youre overflying the airport. It would be unreasonable to expect planes to know about all airports below the planned routing, and adjust the airspeed accordingly.

 

These are just my thoughts about this subject, and is in no way the official answer. I'm certainly no expert when it comes to FAA procedure, I simply used common sense when trying to find an answer.

[phoenixphire 50]

One real world pilot will be able to answer this. It is an interesting question and I am curious to know the answer as well. Both posters make good logical guesses.

[kevinh 409]

The speed limit altitude is relative to sea level reference pressure, not terrain or airfield height. Exactly like an ATC assigned altitude, and for the same reason.

[scandinavian13 5,192]

Guys, I don't think the speed is the question. The way I read it, he's talking about the checklist items like landing lights, seatbelts and so on.

 

Speed in the United States is definitive and doesn't require anyone who flies to step in: no greater than 250 under 10 (with exceptions for minimum safe speeds), 200 under B shelves, or as restricted by NOTAM (for SFRAs, etc).

[killkenny1 22]

Guys, I don't think the speed is the question. The way I read it, he's talking about the checklist items like landing lights, seatbelts and so on.

 

Speed in the United States is definitive and doesn't require anyone who flies to step in: no greater than 250 under 10 (with exceptions for minimum safe speeds), 200 under B shelves, or as restricted by NOTAM (for SFRAs, etc).

For landing lights, seatbelts, etc. I still think it's 10000 feet. Those are the standard procedures after all.

As for approach speed, I think charts should be looked upon.

Not a RL pilot, just seems logical this way.

[fstulm 4]

Hello all

 

I am a real world pilot and even though I have not yet operated at a very high altitude airport here is what I think:

1. Usually most of the Class B airports have their top of airspace less/up to 10000MSL hence the lights rules of see and be seen.
    
   
2. If we get into a situation like in El Alto/La Paz where the field is at approx 14000 MSL, then the lights on rule would probably apply no lower than the altitude where the designated airspace ends. I don't have the charts with me now but for example, if the airspace for El Alto is 4000 above the field then the lights should be kept on till at least approx 18000MSL
    
   
3. Another criteria is a situation like La Paz could be to have lights on till the transition level which abviously will be higher than 14000.
   

Ionut "John" Micu

[NGXfanatic 85]

Thanks for the responses everyone. I know real life pilots have not chimed in, at least not yet, but I believe you all make perfect sense. It would not be feasible for the pilot to have to keep track of the altitudes of the airports below during overflight to determine if they are below or above the 10,000 "red line" and have to slow down to 250 kts, at least if they are just passing overhead the airfields on their way to their true destinations. Even though I am not concerned with the 250kt speed rule as a pilot overflying along the way airports, that detail itself is relevant to my query.

 

It appears the 250kt rule at 10,000ft rule would apply to all airports, regardless of their elevation, by default. I'm sure that it is possible that pilots would reduce speed to 250kts at higher altitudes at such destinations, but they would know because it would be noted on their charts or ATC would demand it. I have a feeling that at KJAC, arrivals may have to reduce to 250kts or slower at say, 14000 ft, 30 nm from the IAF because the runway elevation is 6500ft. I don't know if the speed reduction is fact, but the charts do depict having arrivals descend to 14000ft shortly prior to IAF interception.

 

Anyhow, thanks for the replies, as it pretty much satisfies my curiosity!

[fstulm 4]

Domingo,

 

I am real life pilot and besides the 250/10000 there is another one that really solves the problem regardless of altitude: in controlled airspace such as Class B, limit is 200 unless otherwise given/special request/equipment requirement. I can give you exact FAR part but I don't have it with me now.

 

For example, a clean heavy 744 cannot go with 200 IAS.

 

Ionut "John" Micu

[FLEX1978 373]

I really don't understand this obsession with 250 knots below 10000ft

[fstulm 4]

Rob,

 

What do you mean obsession? As I'm sure you already know, it's a rule to obide by... I think this rule becomes a challenge for some when instead of being fast and high by 10000 they are still on the ground and above 10000. Woops!

 

Ionut "John" Micu

[Guest BeaverDriver]

Rob, this isn't an "obsession". Think of it from an approach controller's point of view for one example. You get an airplane (let's say in this case a 737) about 30 to 40 nm out if I remember correctly, who is transitioning from high altitudes and high speeds. In front of him at about 15 nm out from the active runway just joining the ILS is another airplane that is now slowing to approach speed, which could be something like 120 kts (for argument's sake, but could be a lot slower if it's a 182 or something similar). If the 737 were to hold a speed something close to max, he'd be moving roughly 5 miles a minute. Straight line distance to the airport that's about 6 minutes from 30 nm out. Meanwhile, the 120 kt guy 15 nm out is 2 miles a minute for the last 15 nm, or 7 minutes. Even with a lot of vectoring around, that 737 is going to have to do some fast and fancy braking to keep from bumping into the Dash 8 just intercepting the ILS, never mind getting slowed up enough to be able to start extending flaps and what not (and there's another thread here were some have noted it's hard to slow these things down - and they are now-a-days!). Passengers may not like being thrown forward in their seats all that much during a rapid deceleration, assuming you could actually pull one off. Anyway, that example is with 2 airplanes only. What about the guy 5 miles ahead of the 737 that is starting to get slowed up to keep from bumping into the Dash 8 and to keep from zooming right through the ILS path; and the guy 5 miles ahead of him who is going slower yet. Oh, and then there's the 747 at max landing weight 5 miles behind the 73 who has an approach speed of 180 kts! You get the idea. It's all about trying to keep everyone separated, and the only way you can do that is to have everyone moving at speeds as close to each other as possible. It's not an obsession per se; its a way to keep airplanes from becoming to "intimate" with each other :smile:.

[scandinavian13 5,192]

I really don't understand this obsession with 250 knots below 10000ft

 

I don't either, and a great number of them don't really understand the true application of the rule either.

 

What do you mean obsession? As I'm sure you already know, it's a rule to obide by... I think this rule becomes a challenge for some when instead of being fast and high by 10000 they are still on the ground and above 10000. Woops!

 

I'll let Rob speak for himself, but I'll state my issues with the rule:

1 - most of the time, simmers grossly misunderstand the rule

2 - of all of the rules, it seems that this is the only one they understand or follow - we'll stick to the 250/10 "rule" (I say "rule" because it has exceptions, which most of the simmers don't understand), but completely ignore (or at least don't seek out information on) all the others

 

...and the max airspeed IN the Class B airspace is not 200. You're misquoting FAR 91.117© and (d). If you really are a 744 pilot, you'd know that. That restriction is for aircraft flying under the Class B shelves. This is exactly why I have issues with the obsession with the 250/10 rule, as I stated above. There is a severe lack of understanding of the rules.

 

Sec. 91.117 — Aircraft speed.

 

(a Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10,000 feet MSL at an indicated airspeed of more than 250 knots (288 m.p.h.).

 

(b Unless otherwise authorized or required by ATC, no person may operate an aircraft at or below 2,500 feet above the surface within 4 nautical miles of the primary airport of a Class C or Class D airspace area at an indicated airspeed of more than 200 knots (230 mph.). This paragraph (b does not apply to any operations within a Class B airspace area. Such operations shall comply with paragraph (a) of this section.

 

(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.

 

Rob, this isn't an "obsession". Think of it from an approach controller's point of view for one example. You get an airplane (let's say in this case a 737) about 30 to 40 nm out if I remember correctly, who is transitioning from high altitudes and high speeds. In front of him at about 15 nm out from the active runway just joining the ILS is another airplane that is now slowing to approach speed, which could be something like 120 kts (for argument's sake, but could be a lot slower if it's a 182 or something similar). If the 737 were to hold a speed something close to max, he'd be moving roughly 5 miles a minute. Straight line distance to the airport that's about 6 minutes from 30 nm out. Meanwhile, the 120 kt guy 15 nm out is 2 miles a minute for the last 15 nm, or 7 minutes. Even with a lot of vectoring around, that 737 is going to have to do some fast and fancy braking to keep from bumping into the Dash 8 just intercepting the ILS, never mind getting slowed up enough to be able to start extending flaps and what not (and there's another thread here were some have noted it's hard to slow these things down - and they are now-a-days!). Passengers may not like being thrown forward in their seats all that much during a rapid deceleration, assuming you could actually pull one off. Anyway, that example is with 2 airplanes only. What about the guy 5 miles ahead of the 737 that is starting to get slowed up to keep from bumping into the Dash 8 and to keep from zooming right through the ILS path; and the guy 5 miles ahead of him who is going slower yet. Oh, and then there's the 747 at max landing weight 5 miles behind the 73 who has an approach speed of 180 kts! You get the idea. It's all about trying to keep everyone separated, and the only way you can do that is to have everyone moving at speeds as close to each other as possible. It's not an obsession per se; its a way to keep airplanes from becoming to "intimate" with each other :smile:.

 

None of us are questioning why the rule is there. We're questioning why simmers have such an obsession with that one rule, and believe that there are no exceptions, among other issues.

[FLEX1978 373]

Guys I'm passing through.. My comment is in regards to a lot of flight simmers that don't really seem to fully understand how this restriction is applied real world. It does seem like an obsession to me amongs simmers who have no real world operational experience.

 

I wish I had a bit of time to go into depth but I don't, hense my brief comment.

 

Regards