[nateberkopec]

I volunteered in SAR for five years, and the topic of W3W would occasionally come up.

For me, it’s just already damn hard to make sure you can hear numbers correctly over the radio. In marginal conditions, it’s a hell of a lot easier to use numbers (and requires less time due to not having to repeat or ask for clarification).

Do I really want to be trying to say “arrows.midst.senses” over a handheld radio?

[PeterisP]

Especially since "arrows.midst.senses" and "arrow.midst.senses" are two different locations, and if you mishear it as "arrows.midst.sends", that's yet another different valid location.

Really, there's all the research done (since the invention of early radio?) on what makes a phonetic alphabet or phonetic code usable in noisy conditions, and instead W3W effectively plants a field of rakes in front of blindfolded people.

[margalabargala]

Or worse, "arrows.midst.senses" and "arrows.mist.senses"

[gorlilla]

Arrows.missed.census

[simonjgreen]

Very similar experience, decade in volunteer SAR with a lot of police and fire overlap.

I hold exactly the same opinion as you, however what is very telling us that the police and fire services love it. I think that's because of the accessibility of the system rather than the underlying algorithm or communication.

I am also coming to see w3w locations written more and more as a more accessible alternative to coordinates, especially in land sales and forestry situations.

I do particularly hate that government services and agencies are becoming reliant on a commercially licensed pattern. It does not tick the sustainability tickbox for me.

I hate it as much as I love it.

[switch007]

SAR = Search and Rescue

[permo-w]

poor implementation aside, the format has its advantages over numerical coordinates

besides the greater public awareness of w3w amongst certain demographics compared to coordinates, they may be harder to hear, but it's much easier to read out three words correctly than it is 16-18 numbers

the thing with words is that they're easy to hear in context, but take them out of context and they're often indecipherable

perhaps a system that gives each square a coherent-sounding sentence could be tried, although I'm sure that would have its difficulties too

[CapitalistCartr]

Yeah, to avoid that confusion, it won't be three words when spoken.

"arrows.midst.senses"

Will become "Alpha, romeo, romeo, oscar, whiskey, sierra. Mike, india, delta, sierra, tango. Sierra, echo, november, sierra, echo, sierra".

[inopinatus]

Coherence is unfortunately a subjective matter, as in the phrase “too.much.butter” which is syntactically valid but has no comprehensible meaning.

[permo-w]

I enjoyed this

[thakoppno]

The fifth decimal of a GPS coordinate resolves down to 1.1 meter.

Ten numbers doesn’t sound much more difficult than three words to me.

[mlyle]

12.34567N 89.01234W is 14 digits, 2 points, and 2 signs or letters.

Earth is about 2^49 square meters. If you want precision of ~8 square meters, you're going to need to convey 46 bits of information (or use an optimization that gives less resolution over oceans, etc, but that's only going to be a small win-- a bit or two).

46/3.3 = 14 digits, but the latitude/longitude coding is a little less efficient because it's not uniform. A plus code does it in 11 characters (not including the plus) worth each 4.32 bits =~ 47.5 bits.

[permo-w]

if Earth sqm = 2^49: to address a single metre, we'd need 49 bits. log_10(2^49) = 14.75 so we'd need 15 spoken decimal digits for 1 sqm. for 8m do log_10(2^47)

[mlyle]

> if Earth sqm = 2^49: to address a single metre, we'd need 49 bits.

Yes-- that's why I said it was 46 bits for an 8 square meter area (because this is about the size of area you care about for this problem-- W3W is 9 square meters).

> for 8m do log_10(2^47)

No, because 2^3 = 8, so one does log_10(2^(49-3)) and gets 13.8. 46 / 3.3 =~ 13.9 works because 1/log_10(2) =~ 3.3.

[blacksmith_tb]

I'd say that's not so different from using IP addresses instead of DNS - generally not too popular (and that's for IPv4...)

[pharmakom]

Can you suggest an iOS app that can give geo coordinates appropriate for S&R? Ideally whilst offline?

[sakjur]

The built-in Compass app shows your longitude, latitude, and elevation in addition to providing heading.

[charcircuit]

Why are you not sending text messages to each other if it is so hard to understand? You can have plenty of error correction to make sure the message always is correctly received.

[Mordisquitos]

If they are in a situation in which they can send W3W coordinates by text message, then they are in a situation in which they can send ordinary numerical coordinates by text message.

[charcircuit]

I don't care what they use. I am stating they are using the wrong protocol if there is a chance to introduce errors when sending a message.

[Mordisquitos]

And I'm implying that there are situations where they cannot take the luxury of communicating by text with the extreme care required not to make the slightest typo in W3W.