Transfer times

More maths - so hit the ‘Back’ button now if you wish!

I have been experimenting (with a couple of classes) with producing ‘lower bounds’ for transfer times between summits.

Using OS grid references and Pythagoras’ Theorem, we worked out a direct linear distance from the parking spot to the summit/activation point. This being a straight line rather than following any likely path is why the result is a ‘lower bound’ rather than a definitive answer.

We then used Naismith’s Rule to calculate the walking time. Naismith’s Rule is known and accepted to be optimistic, hence strengthening the fact that this will be a lower bound. To obtain the full time for summit to summit transfer, the 1st summit descent Naismith time is added to the driving time courtesy of Multimap (you just enter grid references of parking spots it it works it all out for you), and then added to the 2nd summit ascent time (also Naismith).

The final bit, is to test the theory against the practice. Here are the results:

The Cloud G/SP-015 - summit SJ904637 - parking spot SJ907633

NS distance = 0.3km, EW distance = 0.4km; direct distance by PT = 0.5km

Gun G/SP-013 - summit SJ970615 - parking spot SJ967609

To be continued…

In reply to M1EYP:
I wish I’d had a maths teacher like you Tom… A level maths might even have been enjoyable!

It was my Physics teacher that sparked my interest in ham radio with a long wire and a dubious QRP CW “rig” that he used to fire up at lunchtmes occasionally. I only ever remember seeing him make a couple of QSO’s…

Anyway I digress… Is this all done on paper or do they put it into a spreadsheet (having worked out the various formulae)?

73 Marc GØAZS

Gun walk continued:

NS distance = 0.7km, EW distance = 0.6km - direct distance by PT = 0.922km

Driving time between parking spots, according to Multimap: 9 minutes

The Cloud vertical descent = 33m

Gun vertical ascent = 27m

Total walking time by NR = 1.422km / 4km x 60mins + 6mins = 27mins

Total transfer time = 27mins + 9mins = 36mins.

Yesterday:

M1EYP last contact SP-015: 1458z First contact SP-013: 1536z

Transfer time = 38mins.

Interesting (to me)! And yes, the pupils do then convert their algebra into an Excel formula and type into a spreadsheet.

I was actually quicker than that though, for there were further unanswered CQ calls from The Cloud, and I waited on Gun for a few minutes for the S2S with Dave. Perhaps I ought to factor out the height parameter for descents.

It will be interesting to compare theory and practice for more significant transfers, like Helvellyn to Skiddaw that I did recently. Of course, there is now a wealth of data opened up in the Database that I could chuck at the kids for fuller analysis!

Work is fun!

In reply to M1EYP:

Tom,

After each activation day I record actual times against my estimates on the Excel schedules I’ve prepared. You are welcome to look at them if they would be of any use. Must say I add a bit to my Naismith’s calculations - to allow for “photographic opportunities”. Try factoring that into your calculations!

73, Gerald

I agree Gerald. In terms of a normal day out walking, relaxing and activating with my kids, I tend to use “Double Naismith” as my walking time estimate. This works quite well. On my own, or with just Jimmy, and when we are trying to get as many in as possible, then Naismith is quite acurate.

What I am interested to do here is determine the quickest possible times to transfer between consecutive activations.

My transfer time between last contact Cloud and first contact Gun was 33 minutes today, so just ahead of Naismith’s and Multimap’s 36 minutes.

This morning, the “transfer time” between last contact Cloud and first contact Gun, was again 33 minutes. This pair must offer one of the fastest transfers that is possible in SOTA.

What is the fastest transfer in YOUR SOTA activator log?

(Definition: time in minutes between last contact on one summit and the first contact on the next - the Show All QSOs option on your Database activator log will contain all the data).

Yep, gathering more data for my students.

In reply to M1EYP:

This pair must offer one
of the fastest transfers that is possible in SOTA.

This could be true in UK Tom, youd get a shock if you looked somewhere like DM/TH where youd be talking less than 33 mins - a lot less if you were on a bicycle.