Question regarding instruction from Manchester approach

[Marc Sieffert]

Hi, I got an instruction from Manchester approach that I could not understand (from a language perspective since I am not native English speaking but probably also from the content point of view...)  - See link below - The first part before descend 5000 feet...

Something with 35 ...???  considering that I was 20 NM from the airport I am not sure what 35 could have been.. probably not 35 NM to be tracked before decsending... Anybody could clarify this? Thanks a lot!!

https://drive.google.com/file/d/10fbnawDPniIZNSCiqn-O3nrj10VHV5tj/view?usp=sharing

[Koen Meier]

While you might be 20 nm straight distance from the airport. he is saying that it will take you 35 track miles to get there due to vectoring.

[Trevor Hannant]

When a controller gives you track miles such as on this occasion, it's to allow you to plan your descent accordingly.   These are used to aid in providing a Continuous Descent Approach (CDA) to traffic inbound to an airfield rather than have you perform a rapid descent then fly level for a period before another descent etc.

 

[Andreas Fuchs]

And just to complement the previous replies: a standard vertical 3 degree path equals descending 1000ft per 3 NM. So, if you were at a height of 6000ft above the airport, you'd need approximately 18 NM to reach landing elevation on such a standard vertical path. Better round it up to 20 NM to stay on the conservative side.

[Marc Sieffert]

Hi I have two more questions regarding 2 instructions;

The first one is a request to descend to  FL 120 to the level TNT. Is this how in english you request to reach FL120 when reaching TNT?

The second is to keep a speed until track DME... then he said this means 10 NM DME... Could somebody explain this why track DME  means 10 NM DME?

https://drive.google.com/file/d/11A2xRJufp04Cfc_zKRqwTN6O3RxvdlYl/view?usp=sharing

Thanks!!

Edited February 5, 2021 at 08:45 PM by Marc Sieffert

[Trevor Hannant]

The first instruction was

"when ready, descend FL120 to be level by TNT"

So yes, at your TOD point descend be level 120 at or just before that point (not descend now and be level 40 miles before as some people do! 🙄😂 )

His second instruction was:

"speed 180 until 10DME"   

it then sounds like he wasn't sure whether it was read back correctly hence why he asked you "just confirm it's 10DME, 1 0 DME"

[Nick Marinov]

38 minutes ago, Marc Sieffert said:

Hi I have two more questions regarding 2 instructions;

The first one is a request to descend to  FL 120 to the level TNT. Is this how in english you request to reach FL120 when reaching TNT?

The second is to keep a speed until track DME... then he said this means 10 NM DME... Could somebody explain this why track DME  means 10 NM DME?

https://drive.google.com/file/d/11A2xRJufp04Cfc_zKRqwTN6O3RxvdlYl/view?usp=sharing

Thanks!!

You are correct for the first one. "Descend FLXXX level by [WAYPOINT]" means be at this level when you are passing [WAYPOINT].
If you are told "Descend FLXXX level abeam [WAYPOINT]" this will mean that you are on a heading, but the controller wants you to be at that level when you sort of reach the waypoint while flying the heading (you can still see the waypoint on the navigation display and eyeball the descend via that or use a formula to calculate your descend rate depending on the distance to the waypoint.

If you are given, for example, "Speed 160kts until 4 DME" means to maintain this speed until you pass the 4 mile mark on the ILS.

Edit: Trevor beat me to it.

Edited February 5, 2021 at 09:24 PM by Nick Marinov

[Andreas Fuchs]

DME = Distance Measuring Equipment. Associated to a VOR or ILS station.