QKRTHNU
Guest
#1. Why is it that Group desinations don't match up @ NDLs?
ie. On the USN tables:
70ft NDL is 50min and leaves you at group I
90ft NDL is 30min but only puts you in group H
Why doesn't the 90ft NDL put you in the same pressure group as the 70ft NDL?
#2. This question is in regards to using the tables for multi-level dives. I read a post that said it was accurate to be "Reading the Tables Sideways" to calculate a multi-level dive. http://www.scubaboard.com/showthread.php?s=&threadid=9625&highlight=multilevel+dives+AND+Tables
If I wanted to use tables to plan a multi-level dive, would this be the correct way to do it?
Ficticious dive profile:
90ft for ~18min (GroupF)
Move up to 40ft
Look at table find equivilent 40ft time for group F (50min)
I now have 150min left on NDL according to USN NDL of 200min @ 40ft.
Is this an accurate way to use a table for a multi-level dive? This makes sense to me, but it flys in the face of the group desination/NDL question above.
Thanks!
ie. On the USN tables:
70ft NDL is 50min and leaves you at group I
90ft NDL is 30min but only puts you in group H
Why doesn't the 90ft NDL put you in the same pressure group as the 70ft NDL?
#2. This question is in regards to using the tables for multi-level dives. I read a post that said it was accurate to be "Reading the Tables Sideways" to calculate a multi-level dive. http://www.scubaboard.com/showthread.php?s=&threadid=9625&highlight=multilevel+dives+AND+Tables
If I wanted to use tables to plan a multi-level dive, would this be the correct way to do it?
Ficticious dive profile:
90ft for ~18min (GroupF)
Move up to 40ft
Look at table find equivilent 40ft time for group F (50min)
I now have 150min left on NDL according to USN NDL of 200min @ 40ft.
Is this an accurate way to use a table for a multi-level dive? This makes sense to me, but it flys in the face of the group desination/NDL question above.
Thanks!