Hi,

On some ILS charts for some Airports, there's two different CAT I minimas, one is normal, and the other one usually has a RVR minima of 400m and it says LTS besides it. So, what does it mean, and how does it affect Aircraft in such way that it makes them able to have a lower RVR minima?

 

Thanks in advance!

Usually LTS is the abbreviation for lights. I'm trying to remember if i've seen it in that section, could you post an example?

On another note, runway lighting can make the difference when it comes to RVR minima. Runway lights and type being operable or inop can increase or decrease RVR requirements. This really becomes a factor when flying in low vis. Some places in Europe, if you can see a certain distance down the runway and lights are operable, you can depart in certain circumstances. The only way to know is knowing the spacing between lights which requires the centerline lights to operable. Interested to see the plate you mentioned. When I flew in the military, the visibility measurement had to be derived from a runway system and converted.

It means "Lower than standard"

Normal ILS RVR 550M

LTS ILS RVR 400M

 

👍👨‍✈️ 

As above, it means 'Lower Than Standard'. Basically permits CAT I ops down to minimum 400m RVR  (the standard CAT I minimum RVR being 550m) provided certain requirements are met, broadly:

- Aircraft equipped with a CAT III approved HUD or autoland system

- LVPs (Low Visibility Procedures) in effect

- ILS approved & flight checked for LTS CAT I operations

- Touchdown and/or centreline lighting operational (would not be required for a standard CAT I ILS)

Sweet, outside of my company minimums. I've either never seen it or never payed it any attention since I can't go that low on vis. The nice thing is with EVS, I can go below minimums to 100ft above TDZ on Cat 1 ILS and S non precisions before the PNF has to see the runway environment with the naked eye. I tell guys you learn something new everyday.