Merits of Block Descents

Hi, all!

I’ve been using a new technique during busy approach times, and I thought I’d share it with you guys.

A lot of people can get flustered when heavy traffic comes in at once, right? You’re not alone. We all encounter it at one point, including myself. Here’s where a solution comes in.

What I’m finding is that giving higher blocks of descent to arrival aircraft helps tremendously with workload and effort. A chaotic session can quickly become orderly when doing so.

To put things in perspective, here’s some math. Imagine 30 aircraft inbound for JFK at FL220 and you give 2,000 feet descent increments every two minutes. Let’s include the theoretical time of arrival at… thirty minutes or so. Take 30 x 10 (amount of descents given within arrival frame to each aircraft). 300 commands given in a 20 minute time frame. That’s astounding, isn’t it?

Now… try FL220 —> 10,000 —> intercept altitude. That’s a total of two commands ever given to every aircraft. 2 X 30 = 60 for the whole thirty minutes. Massive difference! You’ve cut out 240 unnecessary commands!


  • Stops grief and crying during heavy sessions.
  • Pilot can focus on his descent.
  • Pilot doesn’t have to keep stopping and adjusting for a new command. (They hate doing that!)
  • Streamline orderly traffic flow.
  • Frees controller efforts to focus on maintaining sep and other issues.
  • Etc.

Now, obviously, there are a lot of variables that go into sending those descents. Consider the block altitudes that other aircraft have been cleared to pass through, as well as their approximate position. You don’t want to give a 10,000 block head on to another aircraft who’s been cleared to the same zone. The rate of descents will most likely vary, and there’s no guarantee that they will have the proper vertical sep in time, which is a must.

Use it when appropriate. If you’ve got dozens coming in from all directions, best to keep descents on the lower end to arrange them in line, or else there will probably be a vertical sep bust at one point. Once arranged and orderly, unleash crisp and minimal instructions for great results. That’s been the result of my observations for the last few days.

Hope this helps! Feel free to discuss and ask questions about technique. That’s what we’re here for.


This might work assuming everyone has the same flightplan and is coming in at similar approximate speeds.

You throw it into anything but that and it breaks down like a Jaguar in an off road race.


Great insight! If you have someone cruising at 10,000ft then you can absolutely descend someone from FL400 to 11,000ft, then continue once the conflict is resolved.

There is so much airspace out there! Sometimes just a 10° turn gives someone all the space they need for a top to bottom descent without baby steps.


Absolutely! There’s a lot you can do with the space provided.

Got some great feedback from other controllers flying in Charlotte last evening. Swung them on a downwind to 18C many miles away and sent them to 5,000 from cruising altitude. Reports of -1,500 to -1,900 FPM was the norm, which isn’t even pushing it. Simple turn from downwind to 3,000 on base, then final turn, was all it took. I even had time to make myself tea with six guys in the line! (watching the screen, of course)

I kind of like to throw a contingency altitude in the middle, though, like 5,000. Just in case somebody needs to be vectored to the back while not too low, vertical sep with other guys, etc.

Hopefully, this can empower pilots to be a bit more responsible. They can look at the large block and say… “Hey, this guy trusts me to get to intercept altitude in time. Let’s do it!”


Can you do a tower talk video while using this method?


Absolutely amazing! Thank you for putting this out there @JoshFly8


As I outlined prior, we have contingency plans for those kind of issues. There are a lot of ways to work around anything that could occur with the tools we have.

Experience is key. Try a hand on TS2 and see how it goes. Once you spend a significant amount of time going through the correct motions, you’re prepped for a lot that could come your way. You can feel the line moving and envisioning where people will end up and when, even after giving such large block altitudes.


Absolutely. Airshou has been reapproved recently, so I can start making videos again. Just need to find the time and frame for a good session without too many interruptions. Usually takes me about a half dozen takes before I can get through.


Whenever you can please do. Your videos are extremely helpful. :)

This is used IRL, hoping that block assents will occur during global.

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Fascinating post, Josh. I usually use smaller increments, especially below ten or fifteen thousand, but I will definitely give this a try! Thanks for the tip.

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@JoshFly8, can you comment on the VS of descending planes? I have not been an approach controller long but the first thing that has been clear to me is that pilots are usually too high and descend too slowly. I had to vector some a little further out to give them time to get down to the right altitude.

If you were to give me an 18,000 to 10,000 descent does that mean ASAP or get there within a certain amount of time?

I do think this is great insight but not feasible taking speed and elevation of aircrafts in a busy region

That is the pilots fault. If you are too high and too fast, enjoy being vectored out and around or put in a hold to descend.


I want to share my guess, your VS should be at least your ground speed / 2. (e.g 270GS / 1300-1400 VS)

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10/10 I hate this. Brilliant work @JoshFly8

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@JoshFly8, can you comment on the VS of descending planes? I have not been an approach controller long but the first thing that has been clear to me is that pilots are usually too high and descend too slowly. I had to vector some a little further out to give them time to get down to the right altitude.

That’s fine. If planes can’t descend appropriately to meet the localizer in time, that’s their problem. They can either enjoy being vectored to the back of the line or placed in a hold if otherwise. My tests from CLT had most people go from an average of -1,500 to -1,900 FPM from FL180 at about forty miles of total track flying to the localizer. @Chris_S

I just want you to get down in an appropriate time frame. Pace yourself to meet the intercept altitude by the time we turn you to intercept. One guy did -3,000 yesterday and found himself at 3,000 thirty miles out from the field. If you want to do that, then it’s your problem. I suggest getting familiar with calculating rates of descents. @hmkane


Been using this approach for 3 sessions now, and it definitely saves time, and I believe provides better service! It does shift some work back to the pilot, as the descent rate is now in their hands! Too fast, and you’re crawling around at intercept altitude for 20mi… too slow, and you’ll be put in a hold, or vectored back a few aircraft.

FYI… one of the reasons we’re moving to this method is because an airline pilot being vectored by one of us was getting frustrated with the small altitude adjustments! He said if it’s clear below me, give me the final altitude, and let me figure out the descent rate!

So… now you know… this is moving closer to what’s done in real life!


We have our ways. That’s what speed commands are for: maintaining separation, spacing, and sequencing. ;)