TDI Adv Nitrox and Deco Procedures with a Peregrine

[BjörnBear]

When I did my AN/DP course the instructor advised that he, and most tech divers I'd likely be diving with, would be using shearwaters, but that I could use whatever computer or depth guage/timer I wanted, as long as it was capable and I knew how to use it. In the end, I chose to do the course using tables and two recreational computers that I already owned in guage mode.

My choice was mainly motivated by a desire to really wrap my head around proper dive planning and excecution, but I wasn't upset about the fact that I could delay spending a couple of thousand extra until later.

My point being, some instructors may require certain equipment based on how they teach the class. But there are instructors out there who are happy to work with what you have, within reason.

 

[ToneNQ]

I did AN/DP with two different computers in gauge mode and using tables. As a technical diver I use a Perdix and a Petrel2, but that is because they support Trimix and CCR. The Peregrine does everything you need for AN/DP and uses ZHL-16C. It's perfect for that level of diving if you have no intention of going further. Plan your dive, dive your plan, have redundancy, but how you achieve these is really up to you.

If you download the TDI course standards for AN and DP, you'll see its not a TDI requirement to use any specific gear. The instructor may have a requirement but that is not TDI driven, that is the LDS.

 

[RyanT]

I think the other folks here have already given good advice, so I'll just reiterate, it does sound like the shop is more focused on selling you gear than good education. When I did my AN/DP course, I learned with a single computer. My back up was a bottom timer with my dive plan on a slate. Find another instructor.

Here's something else to consider.... AN/DP will certify you to 150'. Lots of folks these days (myself included) add some helium at substantially shallower depths than 150'. Even in the AN/DP range, you may find that the Peregrine is lacking without the helium option. You very well may end up looking to sell the Peregrines to up grade to the Perdix.

 

[Capt Jim Wyatt]

One of my local dive shop has told me that I can't take the TDI courses with the Peregrine and that I can take it only if I buy two Perdix, no other options because the Peregrine doesn't' have the right algorithm (I believe they refer to the Optional VPM-B algorithm).

So wrong...You can take it with no computers at all. I would avoid that shop...

 

[kensuf]

Remember, in technical diving we follow the rule of thirds, so you need three computers. One for each wrist and then a third on an ankle. Redundancy is key.

In all seriousness, while I strongly recommend that my students have a shearwater, you don't need a computer at all, two bottom timers and tables are sufficient. Most of my students show up with a single shearwater and an older computer that can be run in gauge mode.

 

[Jim Lapenta]

For AN/DP I do recommend Shearwater. I use a Predator and one of the two Perdixes I own. Or one of them and my OMS bottom timer. Students are free to use any computer they like as long as it won't lock them out. If that's a possibility then it has to be able to be used in gauge mode. We are going to cut tables anyway on Multi-Deco and look at the differences between models anyway and follow the tables we cut.
We'll also cut contingency plans.
I'd run from that shop.

 

[rhwestfall]

When I did my AN/DP tech training (NAUI), the instructor mandated VPM to be used, and we had to use V-Planner. Both of us got SW Petrels.

I wonder where the stance is now...

 

[Jim Lapenta]

When I did my AN/DP tech training (NAUI), the instructor mandated VPM to be used, and we had to use V-Planner. Both of us got SW Petrels.

I wonder where the stance is now...

It depends on the instructor. I still use VPM-B personally for my dives because it's worked for me for the last 12 years and it allows me to do everything I want to do. I do cover Gradient Factors in class and talk about preferences among tech divers. It is Deco Theory after all. My original tech training was through NAUI using the paperback NAUI RGBM Tables. That was a thick book.

 

[rddvet]

Skip that shop and move on. I would think any computer and a backup bottom timer/depth gauge would be suitable for any an/dp class. I had 2 computers but it wasn't a requirement for my class. I'd be sad if tdi requires it now, but it sounds more like it's just a crappy shop.

 

[Capt Jim Wyatt]

I'd be sad if tdi requires it now, but it sounds more like it's just a crappy shop.

TDI does not require it.