Slowing at/by 10K

[hydroflyer]

This note immediately follows the above quoted AIM section 4-4-9(d):

NOTE-
Leveling off at 10,000 feet MSL on descent or 2,500 feet above airport elevation (prior to entering a Class C or Class D surface area) to comply with 14 CFR Section 91.117 airspeed restrictions is commonplace. Controllers anticipate this action and plan accordingly. Leveling off at any other time on climb or descent may seriously affect air traffic handling by ATC. Consequently, it is imperative that pilots make every effort to fulfill the above expected actions to aid ATC in safely handling and expediting traffic.

http://www.faa.gov/ATpubs/AIM/Chap4/aim0404.html#4-4-9

 

[81Horse]

Mahalo, Hold West. Good explanation from the other side of the mike.

It probably bears saying that the procedure allowed for by the AIM greatly predates current aircraft, and flight management systems. It also dates back to a time when in-trail spacing was less of a concern than it is today.

Here's the same AIM section on rate-of-climb:

... Descend or climb at an optimum rate consistent with the operating characteristics of the aircraft to 1,000 feet above or below the assigned altitude, and then attempt to descend or climb at a rate of between 500 and 1,500 fpm until the assigned altitude is reached. If at anytime the pilot is unable to climb or descend at a rate of at least 500 feet a minute, advise ATC. ...

 

[Say Again Over]

At the cost index we use it's not that much of an issue, STARS and ATC instructions usually impact our speed well before 10K, how bout 200 south of ORD: "Bus123 turn left heading 270 for sequencing", yikes.

 

[HS125]

Well the AIM isn't the "how to operate book" it's more of a book of guidelines, I feel that a majority of new guys will now leave this thread thinking it's perfectly normal to come streaking in at 340 KTS to 10K and stop there while they bleed off speed, WRONG, that is not how to operate (reference xTWA conversations with ATC), and that is not what the AIM is advocating.

Wow, that's a pretty bold statement! I guess that myself and the several other hundreds of pilots that I have flown with over the last 20 some years need to go back to school.

 

[HS125]

Yeah but leveling at 10 to slow is weak 'n' whimpy and subjects the pax to a less than optimum ride. Real men know exactly how to manipulate V/S so the nose doesn't do wild pitch excursions, and the airspeed will bleed off to 250 at 10 during a decel maneuver while still indicating 1,000 down.

When done properly, leveling at 10,000 to slow to 250 does not subject the pax to an uncomfortable or less than optimum ride. Not properly planning your decent and having to use the speed brakes or do non-normal maneuvering is weak and wimpy.

 

[Hold West]

Quote:
Originally Posted by Say Again Over
Well the AIM isn't the "how to operate book" it's more of a book of guidelines, I feel that a majority of new guys will now leave this thread thinking it's perfectly normal to come streaking in at 340 KTS to 10K and stop there while they bleed off speed, WRONG, that is not how to operate (reference xTWA conversations with ATC), and that is not what the AIM is advocating.


>Wow, that's a pretty bold statement! I guess that myself and the several
> other hundreds of pilots that I have flown with over the last 20 some
> years need to go back to school.

Well, from my perspective and what the FAA teaches controllers is that AIM is essentially that, guidelines in how to apply the FARs and other documents that actually regulate aviation.

In fact, the preface to AIM itself says:

"This publication, while not regulatory, provides information which reflects examples of operating techniques and procedures which may be requirements in other federal publications or regulations. It is made available solely to assist pilots in executing their responsibilities required by other publications."

Emphasis added by me.

Just like at work, I'm always going to look for the underlying regulation before going off what the AIM says, and quote that instead.

 

[Say Again Over]

Thanks for bailing me out.

 

[Say Again Over]

HS125, don't get me wrong, I have used that procedure also, the last thing I need is a violation from exceeding the speed limit below 10K, normally it's something that happens due to ATC interference, if traffic is not a factor I and others I fly with will simply dial in 250 around 12K and presto, going through 10 it happens. If you like waiting til 10K it looks like that is your prerogative depending on what part of the AIM you look at.

 

[Vector4fun]

I don't know why a controller wouldn't anticipate a short level-off, at least half the crews or more do it. It's also mentioned in the Controller's Handbook.

See Note at end of section:


FAA 7110.65, 5-7-1 (c)

c. Simultaneous speed reduction and descent can be extremely difficult, particularly for turbojet aircraft. Specifying which action is to be accomplished first removes any doubt the pilot may have as to controller intent or priority[SIZE=-2]. [/SIZE]Specify which action is expected first when combining speed reduction with a descent clearance.
1. Speed reductions prior to descent.
PHRASEOLOGY-
REDUCE SPEED:

TO (specified speed),

or

(number of knots) KNOTS.

THEN, DESCEND AND MAINTAIN (altitude).
2. Speed reduction following descent.
PHRASEOLOGY-
DESCEND AND MAINTAIN (altitude).

THEN, REDUCE SPEED:

TO (specified speed in knots),

or


TO MACH (Mach number),

or

(number of knots) KNOTS.


NOTE-
When specifying descent prior to speed reduction, consider the maximum speed requirements specified in 14 CFR Section 91.117. It may be necessary for the pilot to level off temporarily and reduce speed prior to descending below 10,000 feet MSL. ​

 

[Gorilla]

Nothing wrong with any of the techniques listed, but all I'm saying is the "fun" technique is to try and minimize pitch changes. I like to descend using V/S, then at the appropriate point, say 12K, roll the speed window back but leave the V/S where it's at. Done properly, the airspeed will slowly bleed to 250 right when you pass 10K. At 250, you may need to increase the V/S slightly, or select LVL CHANGE / CLAMP; hopefully the nose won't need to drop much to maintain the 250.

I just think it's uncomfortable to many pax to do an idle descent, then, as you approach 10K at 2500 fpm, abruptly jack the nose up to slow. Kind of like an MD-80 departing cruise, when the guy selects CLMP and drags the throttles back. WHOOOM, down goes the nose and everyone gets a bit light in the seat, followed by increased G as the bad MD-80 A/P corrects its pitch.

I guess I'm easily amused, and doing things like making a smooth transition at 10K adds a tiny bit of fun or challenge. VNAV is boring.

 

[HS125]

Quote:
In fact, the preface to AIM itself says:

"This publication, while not regulatory, provides information which reflects examples of operating techniques and procedures which may be requirements in other federal publications or regulations. It is made available solely to assist pilots in executing their responsibilities required by other publications."

Emphasis added by me.

Just like at work, I'm always going to look for the underlying regulation before going off what the AIM says, and quote that instead.

While the AIM is not regulatory in nature, much of the information within is compiled from other sources that may not be readily available to pilots without a fair amount of research that is regulatory in nature .

 

[HS125]

Nothing wrong with any of the techniques listed, but all I'm saying is the "fun" technique is to try and minimize pitch changes. I like to descend using V/S, then at the appropriate point, say 12K, roll the speed window back but leave the V/S where it's at. Done properly, the airspeed will slowly bleed to 250 right when you pass 10K. At 250, you may need to increase the V/S slightly, or select LVL CHANGE / CLAMP; hopefully the nose won't need to drop much to maintain the 250.

I just think it's uncomfortable to many pax to do an idle descent, then, as you approach 10K at 2500 fpm, abruptly jack the nose up to slow. Kind of like an MD-80 departing cruise, when the guy selects CLMP and drags the throttles back. WHOOOM, down goes the nose and everyone gets a bit light in the seat, followed by increased G as the bad MD-80 A/P corrects its pitch.

I guess I'm easily amused, and doing things like making a smooth transition at 10K adds a tiny bit of fun or challenge. VNAV is boring.

Anyone who leaves it up to the machine to do the work is just lazy. If you are leaving it to VNAV to do the job for you, you are obvioulsy not interested in giving the pax a good ride. You fly the airplane, the airplane doesn't fly you.

 

[HS125]

HS125, don't get me wrong, I have used that procedure also, the last thing I need is a violation from exceeding the speed limit below 10K, normally it's something that happens due to ATC interference, if traffic is not a factor I and others I fly with will simply dial in 250 around 12K and presto, going through 10 it happens. If you like waiting til 10K it looks like that is your prerogative depending on what part of the AIM you look at.

Agreed, it's all a matter of technique. However, in your previous post, you said that leveling off at 10,000 to slow to 250 was wrong and it is not. ATC expects it and (as Hold West and Vector4fun have pointed out) prepared for it. If ATC needs something different they will tell you. If you blow through 10,000 going faster than 250, its been my experience, the pilot flying isn't minding his/her business.

I personally use both techniques. Which one I use depends on what airport I am flying into and how my decent planning is working out. When the descent is left up to me, I try to plan my descents so that I can come out of altitude at Idle thrust and not touch the throttles until I need to spool up to stabilize the approach around 1,000' AGL. All the while trying to give my PAX the smoothest ride possible.

If I need to bring the throttles up to make it to the runway or use the speed brakes or any special maneuvering to get down, then I didn't do my descent planning propperly.

 

[AdlerDriver]

..........If I need to bring the throttles up to make it to the runway or use the speed brakes or any special maneuvering to get down, then I didn't do my descent planning propperly.

I was with you until this last part.

"Bring the throttles up to make the runway"??

Most companies that have stabilized approach criteria including "Engines spooled" for a good reason.

If you're attempting to stay at idle all the way to the runway, I think you're setting yourself up for a situation where you might need some more power and it won't be there. Maybe I'm misunderstanding your comment.

Idle to the marker or gear down perhaps is a nice goal for style points. Depends on how accomodating ATC is that day.

 

[FL420]

I like to descend using V/S, then at the appropriate point, say 12K, roll the speed window back but leave the V/S where it's at. Done properly, the airspeed will slowly bleed to 250 right when you pass 10K. At 250, you may need to increase the V/S slightly, or select LVL CHANGE / CLAMP; hopefully the nose won't need to drop much to maintain the 250.

Gorilla,

When I first read this I thought you were saying you liked to maintain a constant rate-of-descent as selected on the MCP as you slowed to 250KIAS between 12K and 10K. The only way I could see this happening is if you were descending with power set well above idle which would be very fuel inefficient.

If already at idle the only way to slow to 250KIAS would be to decrease the rate-of-descent below that selected on the MCP by raising the nose until the selected speed is reached. When the selected speed is attained the nose will pitch down again to attempt to regain the selected V/S. Is that your technique?

A lot of check airmen I have encountered really don't like pilots to use V/S, especially below 10K, not only because of the lack of speed protection in V/S but more importantly because you can fly away from an altitude selected on the MCP in V/S. I believe there have been some accidents where pilots inadvertently flew into the ground using V/S with a higher altitude selected on the MCP.