Saturday, 23 February 2013

Snow Joke - Cancelled Navigation Trip

 I had a Navigation session booked for today. Basically I was to fly Rochester to Bewl Reservoir, to Rye, to Ashford and them back to Rochester.

However the weather was not kind to me and hence (another) cancellation was the end result. It is bitterly cold with a NE wind making it feel sub zero. Here are the components of the Met Office 215 form.


As you can see from the far rightermost column the freezing altitude was at the surface level, the next column back from that, that the cloud base was not great and one column back again, that within the areas of snow showers, visibility was not good. I had been watching the weather all week and had my fingers crossed but admit defeat.
One positive today though was I got up early this morning and headed down to the Canterbury area and had my Aviation Medical Examination. I am pleased to say I passed this so I have my medical certificate which is good for another 2 years. This one is different than the last as it is an EASA one. It appears the ECG test is no longer applicable.
Despite the fact my nav trip was cancelled I ran through the PLOG generation. I do this every time. Once through Sky Demon and once through a wizz wheel calculation. I do the wizz wheel one first and then double check for sanity against the Sky Demon one. Of course the latter does some different GS calculation so you never get exactly the same result but good enough to reassure yourself you still know what you are doing... with that wizz wheel!
This was to be the route I would have flown. Perhaps next time ?

Sky Demon PLOG
My routine for a navigational exercise trip goes something like this, it may seem a little laborius to some (err perhaps many) but I am a project/programme manager by day and I just can't help myself :
1) The night before my adventure, I draw my route on both 500k and 250K charts.
2) I repeat this task in Sky Demon, double check the true track calculations in 1, and generally have a look at the weather and notams.
3) I then prepare a manual flight PLOG calculating up to the point of the wind direction and velocity (5th column above).

On the day / next morning

1) Perform the IMSAFE checks.
2) Perform Met Office GA briefing (essentially print off 215, 214, SE Air Met, SE TAFs).
3) Decide on what wind speed and direction I will use for my plog. I typically extrapolate this from the South East Air Met report (I perform a sanity check of this against the 214 report).
4) Open Sky Demon on my computer, ensure it's connected to the internet and let it refresh with the current Weather stats and do its calculations. I then look at the notams, metars and tafs it is giving me and then print the PLOG.
5) Complete my previously prepared manual PLOG by using my chosen wind speed and direction.
6) I then sanity check my manual calculation against the calculations from Sky Demon.
7) I check official NATS Notams

And then generally in my case I ...
8) Contact the flight school and have them confirm my session will have to be cancelled due to the weather!!!!

This was my manual PLOG.... consigned to the cancelled pile.

No comments:

Post a Comment