Day time

phsz said:

Our departure time was 5 minutes prior to sunset from daytime airfield and it was delayed by about 20 minutes.

Where from did you get the exact time of sunset at your departure airport on this particular day?

@pshz

In your first post you said:

Our departure time was 5 minutes prior to sunset from daytime airfield and it was delayed by about 20 minutes

In your post #08 you say:

Airfield has now no restrictions, it was confirmed by airfield administrator just 15 minutes prior to planed departure. So, it's limited only by national regulations.

There appears to be some confusion here regarding the opening hours of this field....

Is it possible that the person that cancelled your flight-plan was similarly "confused"...?

May I suggest a simple, friendly phone call to the unit to find out why the flight plan was cancelled?

The flight cannot retroactively happen, yes it is annoying but no real harm done, I would focus on preventing this from reoccurring next time.

The ICAO definition does not matter, it is still country specific. So assuming your flight was in Latvia, you would have to look at the country regs.

This is the key. Others have correctly quoted ICAO definition of night, but each country makes its own choice as to what is appropriate there.

Just because it's not in the AIP doesn't mean that it doesn't exit. It will be in national regulations somewhere.....

Could you not have refilled?

Is night VFR allowed in Latvia?

I think it's very naughty to just cancel somebody's flight plan.

It happened to me just once: on a flight from Granada to Zaragoza (Spain), with the latter being PPR, I got the office at Granada to telephone Zaragoza for the PPR, which they did right in front of me (in Spanish of course), but when we got loaded up and were ready to start up, we were told that Zaragoza said we did not have permission (!!!) and that they (Zaragoza) cancelled our (Eurocontrol IFR) flight plan. Amazing arrogance... So we flew elsewhere.

Unfortunately anybody anywhere in the world can transmit a Cancel message onto the AFTN, for any aircraft anywhere.

As for The Netherlands the UDP (universal daylight period) is defined in the AIP and is basically from 15 minutes before sunrise to 15 minutes after sunset. If I want to depart from a VFR only airfield in the Netherlands to join IFR I would have to depart during this period as in the Dutch AIP they have included a table with all the airports/airfields and what kind of operations are allowed there. The VFR only airfield would then not allow IFR operations and thus you cannot depart IFR from the field.

For currency (before I had my instrument rating) I remember the 1 takeoff and 1 landing at night as part of the 3 takeoffs and landings. I would fly with my passengers into Antwerp (EBAW) and let wait until it was dark, then talk to the tower that I would like to takeoff and then immediately land on the same runway, then I would taxi back to the apron to pickup my passengers while being current. Now that I have the instrument rating, the night currency is automatically valid with my instrument rating. I only need to have 3 takeoffs and landings in the previous months, which is easy to do.

At the time I was flying night VFR, I often landed after daytime into a remote airfield/airport. The problem with remaining current was the night takeoff.

One other issue to notice is that night VFR rules differ from country to country. E.g. in France you cannot fly Night VFR if there is a forecast of rain, even light rain along your route or at your destination.