runtime table shown in planner

Dirk Hohndel dirk at
Tue Feb 19 14:36:58 PST 2013

Dirk Hohndel <dirk at> writes:

> On Feb 19, 2013, at 1:21 PM, Dirk Hohndel wrote:
>> On Feb 19, 2013, at 1:19 PM, Robert C. Helling wrote:
>>> On Feb 19, 2013, at 10:05 PM, Dirk Hohndel wrote:
>>>> Which makes me think that we may be losing a gas component somewhere while planning.
>>> Good guess. #define DEBUG_PLAN 1 reveals
>>> 	  4:00: 110000mm gas: 100 o2 700 h2
>>> 	 20:00: 110000mm gas: 0 o2 0 h2
>>> oops.
>> 100% N2 is a very odd gas to dive. And no wonder it causes longer deco times…
>> I'll investigate
> No, no, no. Think first, Dirk, then type.
> This is of course not 100% N2. This is our magic value for AIR.
> Additionally, I don't see this unless I type in AIR for the second segment.
> I do, however, now get the plan that violates the ceiling, so I'll work on figuring that out

Found it.

We very carefully track the gases used. We create all the events, we do
all the right things. 

With one MAJOR flaw. 

We always start with o2 = he = 0

That seemed sane to me because if nothing else is set, AIR is the
default gas. But instead we should have always started with gasmix 0 as
that is the gas with which the dive indeed starts. If that is 0/0 -
great, we're on air. But if it is 10/70 then we are NOT.

So the plan was calculated on air but then the plotting of course used
the correct algorithm and therefore correct gas 10/70 which creates
deeper ceilings and longer deco times.

Thank you Jan and Robert for catching this one.

This just shows how serious we are about the "DON'T DIVE THIS PLAN"



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