How to do a steep descent?

[19AB67 16]

Sometimes I wonder how seriously the 260 kph speed limit between 10,000 feet is taken in real life. When I look at actual flights on Flightaware.com it seems that many planes are coming in much faster than that. (Flightaware.com has graphs showing the speed and altitude of real world flights at relatively short intervals) Perhaps Flightaware.com is recording something else, like groundspeed or mph? But in any case, real world planes seem to be coming in pretty fast.

 

Douglas, often the speed is higher than 250kts below 10000ft in real flights.

Never monitored the speed on one of your real flights on the cabin monitors?

Should be of course a little bit more than 30nm out to slow down after the descent...

 

So, what you see on flightaware or flightradar24.com is simply true. ATC might have given permission.

[kevinh 409]

The one thing the FCTM procedure fails to mention is the option of extending the gear, something any 737 pilot would be aware of. This is a far more effective drag producer than the speedbrake if you really have to descend in a hurry. Once at the altitude you want then you can consider slowing down by extending flaps.

 

So basically use LVL CHG, extend speedbrake and extend the landing gear if necessary.

[TailDraggerPilot 17]

you could always "slip" down by crossing over your controls, eg left aileron .right rudder and wont affect your airspeed but Vertical speed is enormous

one problem, you will have 150 full sick bags..

Wrong, it will bring your airspeed down and will descend very fast. It depends on how you do it. Push the nose down will pick up speed but will fall like a brick, bring the nose up lose speed and still fall like a brick.

[Slick Willy 2]

Never ever cross controls in a jet. It's extremely dangerous.

To get down quickly all that is necessary is to pull the speed brakes out. A good daily example of this is coming over the Alps into Torino Casselle. The descent is from FL230 to 4,500ft in about 15dme. Throttle back to 210 kts and apply full spoilers. Your descent rate will be above 2000fpm and fully under control. And, safe!

 

Little more then 2000fpm. Assuming your ground speed was 210kts it would require 4625fpm to meet that. Have a link to the chart?

 

Willy

[KriVa 307]

One of the most common heard phrases on the radio over here is "high speed approved". I don't know about other places in the world, but here it does seem to work reasonably well.

[Spin737 102]

One of the most common heard phrases on the radio over here is "high speed approved". I don't know about other places in the world, but here it does seem to work reasonably well.

I used that all the time in Asia. I've never heard it in the US. Much better than speedbrakes at 250kts.

[killkenny1 22]

Metric speeds? I have never heard about that, are you sure they use that? On a different note, ATC will some times instruct planes to fly faster than the 250kts limit below 10 000, to expedite traffic / help maintaining separation. But its not the norm

Patrick Houghton is right. Russian domestic charts are all metric. Don't know about China, but I have heard they use metric too. And probably CIS too.

Jeppesen usually convert everything to imperial units + provide a "quick" conversion table on the charts.

Other airports might have higher speed on approach. Pulkovo (Saint Petersbug, ULLI) has max 270 knots below 10000 feet.

Here are the charts for ULLI:

Provided by Russia (English and Russian):

http://ivao.e-labs.ru/sites/default/files/charts/ulli.pdf

Jeppesen charts:

http://www.va-uralairlines.ru/charts/ULLI.pdf

[zmak 331]

Wrong, it will bring your airspeed down and will descend very fast. It depends on how you do it. Push the nose down will pick up speed but will fall like a brick, bring the nose up lose speed and still fall like a brick.

 

huh? I can assure that once you have established your descent and locked onto a selected speed, the speed will not increase if applied correctly, however by my statement at the end of the post about 150 sick people kind of indicates that this is NOT something you would choose to do unless you needed down in an emergency . However I have tried this myself in the SIM and works like a charm..

[Slick Willy 2]

huh? I can assure that once you have established your descent and locked onto a selected speed, the speed will not increase if applied correctly, however by my statement at the end of the post about 150 sick people kind of indicates that this is NOT something you would choose to do unless you needed down in an emergency . However I have tried this myself in the SIM and works like a charm..

Doubt it if the 737 would be approved for such a maneuver in any situation. Doing so would probably create a much larger emergency. Such maneuvers place an extreme amount of stress on the vertical stabilizer at the speeds turbine aircraft approach at. A good example would be that AA airbus that had the FO hammering on the rudder.

 

Willy

[zmak 331]

Doubt it if the 737 would be approved for such a maneuver in any situation. Doing so would probably create a much larger emergency. Such maneuvers place an extreme amount of stress on the vertical stabilizer at the speeds turbine aircraft approach at. A good example would be that AA airbus that had the FO hammering on the rudder.

 

Willy

 

yes hammering the rudder wildly with all your strength wouldn't be a good idea in any aircraft but what has it to do with a "slip"? completely different aerodynamics and I find it difficult to believe it would tear the plane up lol. I agree its probably not approved however if you were on fire or engine/ engines out and you were high you would do it as going around wouldn't be an option

 

Anyway it was just something to think about.

Dont want to derail so back on topic.

 

to answer the OP regarding a faster speed when spoiler deployed most probably happens when a higher than normal rate of descent is initiated and then the spoilers are activated.

[wims80 121]

Patrick Houghton is right.

...

Alright cool, thanks for the reference. I knew that they used metric altitudes, but I didn't know that they used metric distances and speeds as well.

[TailDraggerPilot 17]

huh? I can assure that once you have established your descent and locked onto a selected speed, the speed will not increase if applied correctly, however by my statement at the end of the post about 150 sick people kind of indicates that this is NOT something you would choose to do unless you needed down in an emergency . However I have tried this myself in the SIM and works like a charm..

You can hold speed in a slip, you where making it sound like that no matter what the speed wont change. I can do a slip on a base to final with out losing speed I can also being the speed up or down. It all depends on what needs to be done. This is what I do all the time in the pattern so I can do power off approaches. Slips are really meant for small GA planes. Reason not to do it in a big plane is you usual have a 45-75 degree bank.

[zmak 331]

You can hold speed in a slip, you where making it sound like that no matter what the speed wont change. I can do a slip on a base to final with out losing speed I can also being the speed up or down. It all depends on what needs to be done. This is what I do all the time in the pattern so I can do power off approaches. Slips are really meant for small GA planes. Reason not to do it in a big plane is you usual have a 45-75 degree bank.

 

oh dear you are going get your self killed 75 deg bank! insane, if you had to do a slip on base leg in a jet then you really are in big trouble! The idea of a slip in a jet is to get down to a level quickly where normal procedures can proceed.

 

The pilot has to what he has to do even if the manual says no slip. If you are high and running out of fuel errrr stuff the manual

 

do not attempt a slip in circuit in a jet !

 

 

slip example in a jet in real life

http://www.environmentalgraffiti.com/sciencetech/when-death-finds-you/13777

 

As Flight 143 approached the Gimli runway, it was flying too high and too fast for a safe landing. Flaps and slats could not be extended. Captain Pearson executed a ‘forward slip’ over a nearby golf course to increase drag and lose altitude. This is a maneuver designed for gliders and small, light aircraft but it worked!

Read more at http://www.environmentalgraffiti.com/sciencetech/when-death-finds-you/13777#UPMgG5vMAhsHyC5b.99

[TailDraggerPilot 17]

oh dear you are going get your self killed 75 deg bank! insane, if you had to do a slip on base leg in a jet then you really are in big trouble! The idea of a slip in a jet is to get down to a level quickly where normal procedures can proceed.

 

The pilot has to what he has to do even if the manual says no slip. If you are high and running out of fuel errrr stuff the manual

 

do not attempt a slip in circuit in a jet !

 

 

slip example in a jet in real life

http://www.environme...finds-you/13777

 

As Flight 143 approached the Gimli runway, it was flying too high and too fast for a safe landing. Flaps and slats could not be extended. Captain Pearson executed a ‘forward slip’ over a nearby golf course to increase drag and lose altitude. This is a maneuver designed for gliders and small, light aircraft but it worked!

Read more at http://www.environme...G5vMAhsHyC5b.99

I'm not talking about a Jet, I'm talking about a Citabria 7ECA. You can do those kind of slips in them. I like doing short app so I can do slips, there fun.

[vololiberista 205]

Little more then 2000fpm. Assuming your ground speed was 210kts it would require 4625fpm to meet that. Have a link to the chart?

 

Willy

You are confusing airspeed with groundspeed!! This procedure is done on almost every flight from NW Europe. Only the ones that ATC request to turn at TOP descend normally!