CAT calculation for GUE Fundies

[Rainer]

You'll have to forgive me a little as I tend to work in metric, but no.

2 x 0.75 x 2.5 x 11
Use normal SCR for this calculation, so it should come out similar to the old calculation.

So SCR in emergency situations is now taught as 0.75 (instead of the old 1)? If so, agree about it matching the old method.

 

[johnkendall]

So SCR in emergency situations is now taught as 0.75 (instead of the old 1)? If so, agree about it matching the old method.

We tried to simplify it, across the board (rec 1 all the way to Tech 2) so we have one min gas calc that you don't need to remember ascent rules of thumb etc to use.

 

[wetb4igetinthewater]

Remember that as you ascend, you have a new MG gas requirements. So let's say on our way back we hit our turn pressure at 100', we ascend, now we have a different TP that we probably haven't hit yet. When we do, we can ascend, stay until we hit the next TP, and so on. That's what I teach in OW now for dive planning.

 

[mainedvr]

People seem to be confusing two ascent methods.

For a min gas calculation, you determine the ascent time by using 10fpm the entire way, with 1 minute added for "sorting things out" between the start of the incident and starting the ascent.

This is NOT the normal ascent profile.

guruboy thanks that was what I was wondering so it is exclusivly for MG not the actual accent profile.

Again thanks for all the responses.

 

[mainedvr]

We tried to simplify it, across the board (rec 1 all the way to Tech 2) so we have one min gas calc that you don't need to remember ascent rules of thumb etc to use.

Thanks John

 

[C Dub]

We tried to simplify it, across the board (rec 1 all the way to Tech 2) so we have one min gas calc that you don't need to remember ascent rules of thumb etc to use.

You succeeded, this was great change, thank you!! Learned the new CAT calculation in T2 and it is much better/easier/faster.

 

[guruboy]

Remember that as you ascend, you have a new MG gas requirements. So let's say on our way back we hit our turn pressure at 100', we ascend, now we have a different TP that we probably haven't hit yet. When we do, we can ascend, stay until we hit the next TP, and so on. That's what I teach in OW now for dive planning.

OW for who? PADI? All I remember being taught about gas requirements is 500psi.

assuming you use the GUE numbers (S=1.5, ascent at 10fpm), this comes out to 610psi for a standard OW student (which is 60' max).

 

[wetb4igetinthewater]

OW for who? PADI? All I remember being taught about gas requirements is 500psi.

Yes, PADI. I don't believe that an extra 300 psi reserve at the start of the safety stop is sufficient information. As no additional skills are being performed, nothing stops an instructor for providing a GUE-like lecture on dive planning.

 

[eelnoraa]

When calculating minimum gas, Yes. It is calculated assuming that you will ascend no slower than 10' per min.
For a normal ascent, we would ascend at 30' per min to half max depth, and then 10' per min from there.

HTH
John

I didn't read the whole threat. But is this new? I wasn't taught this back. We were taught using the normal ascent profile for calculation, with higher SAC and additional minute for failure handling

 

[Rainer]

I didn't read the whole threat. But is this new? I wasn't taught this back. We were taught using the normal ascent profile for calculation, with higher SAC and additional minute for failure handling

I asked this earlier (a page back). I guess it's a recent change.