Thinking out loud

After a number of weather cancellations, Saturday arrived bright and clear.  Well, clear apart from the lightening and hailstones…

Happily, all those big, bounding cu-nims had wandered their way north by the time I set off for the day’s session on holds.

This required a certain amount of briefing beforehand and I was sincerely hoping it proved simpler in the air than it has on paper as I’ve been applying my brain to it for some while with a rather a lot of foggy confusion remaining.  The bedroom floor is positively littered with little scribbly diagrams of stick-aeroplanes dot-dot-dotting their way towards NDBs drawn in such anguished mental frustration that some of them are stabbed holes in the paper.

However, at least I was fairly confident I knew which hold was which and when to use them, but in case of brain failure Dave had drawn some clues on the DI in chinagraph.

The Cardiff hold is left hand (non standard) but the same works for standard right hand ones as well if you flip the diagram.

Essentially, once you’re inbound to the beacon, you look at where the outbound track falls and there’s your join – no Maths In Public required…

We’d see!

To save time, money and mental workload we were going to do a sort of ‘dummy run’ using the Haverfordwest NDB but flying the pattern of the Cardiff hold.  This had a number of advantages — not least among them being the lack of whopping great hailstorms in that direction.

The plan was to take off, track towards the VOR at Strumble then as soon as we picked up the NDB at Haverfordwest to strike out towards that and track overhead before turning around and having a go at joining the hold.

We’d do once around, then fly the “still pretending it’s Cardiff” alternate procedure, knocking off at 1500′ or so before we became a nuisance to anyone actually flying at Haverfordwest.

So off we went.  A foggles-day as it was beautifully clear behind the clouds.

I still need more practice with accuracy and getting the mental picture of where I am in regards to the various nav aids and made rather a meal of getting on a radial to Strumble.

Tracking the NDB into Haverfordwest was rather simpler as I wasn’t fussed which direction we were going as long as it was towards the field!  It’s when I’m called upon to track a particular QDM that I come a bit unstuck.

Overhead the beacon fairly closely, judging by the speed with which the needle swept round and then back towards it from the southwest.

This put the outbound track of 120 firmly in the Parallel join sector so back to the beacon we went for a right hand turn to 120 to track out the ‘wrong way’ for a minute.

Then right again and back to the beacon for a left turn into the hold proper.

Sort of almost a figure of eight.

What surprised me and perhaps shouldn’t have, was what a steady pace it all happened at.  A minute seems an awfully long time once you’re properly set up and just sort of waiting — and at the same time seems altogether not long enough while you’re frantically trying to remember how the  next bit goes!

At the ‘far end’, a minute’s flying, (and about 2nm on the DME, and with the ADF about 30 degrees off the tail) another rate one turn back towards the beacon.

My turns being less than perfect and the wind more than nil, this was followed by a certain amount of weaving about attempting to regain a QDM of 300…

(Not to mention the occasion on which I stopped the outbound turn short at 210 instead of carrying on around to 120…)

During the inbound turn The Book helpfully advises that one can ‘determine whether you will undershoot or overshoot the inbound track and take appropriate corrective action’.

Dave put a bit more detail on this, advising that halfway round the turn (i.e with 90 degrees to go), the ADF should be at around -70, and with 30 to go it should be around -45.

If it’s greater then you need to tighen up the turn, if it’s less than slacken it off.

I played with this a bit more on “Tim’s Amazing Navigation Simulator” when I got home and it does make a sort of sense.

Someone at work the other day introduced me to the difference between “needing more training” and “needing more practise” — on ADFs and holds I need more practice!

It makes sense but slips from my mind when asked to do it at the same time as fly…

And all accuracy goes completely out the window when it comes to doing anything else at all!

Anyway…

A couple of turns around the hold and then we flew a bodged version of the Cardiff Alternate let down procedure (bodged to keep us above H’west’s circuit!)

The approach charts are starting to make more sense and look less like a beliberately obscure and encrypted treasure map, which is something.

Accuracy still to work on there too as when I pulled off the foggles to see the runway ahead it was… well… there… but I’d have still had a fair amount of manoeuvring to do to put myself remotely on the centreline!

Climbing away, I had a few brief moments to note it had turned into a lovely day before it was foggles back on and tracking away from the NDB.  On limited panel.

Now tracking away and keeping an eye on both heading and ADF is not my strongest suite to begin with, and add to that a neck craning gawp at the compass every half minute and the start of tiredness after an hour’s worth of ‘headwork’ and my tracking left rather a lot to be desired!

Recovery from unusual attitudes also enlivened the trip home – think I need to revise those in general.

Once we were out of range of HAV, we changed to the Brecon VOR to get distance from Swansea (via a small amount of arithmetic – Brecon is 30 miles away) and for the practise got QDMs to Swansea who have a very good, accurate VDF kit.

Foggles came off once we were around Cefn Bryn positioning for downwind and I blinked, trying to reorient myself as Dave did a quick rundown – “Mumbles, Three Cliffs, and there’s the field.”

I think changing for foggles back to visual flight is in a way an odder transition than coming out of cloud.  You’ve consciously kind of cut yourself of from paying attention to what’s out of the window to a greater degree.

Anyway, we touched down with the stall warner squeaking, for a 1:35 hour trip.

The plan is probably to do this in one and a half hour blocks to leave a sensible amount of time for getting anywhere kitted out to do anything!

Next time out is Cardiff for real.

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