Which Raven?

38mm minimum diameter.
Max simulation values: 12,800' altitude, 2040 ft/sec. velocity, 2600 ft/sec/sec. acceleration.

Which Raven - 70/35G dual axis, or 250G single axis?

Reasons, pros/cons, considerations?

thanks, s6

Probably 70g. Apparently they read, just less accurately, above their G limits. Just use mach lockout with baro triggering for apogee, and you should be good.

Now if there are future, higher-acceleration flights in the works, then get the 250G.

You don't really need the lateral measurement.
I usually opt for the 250 unit unless it's unavailable.
With some deployment charges, you get spikes of 70 G's or more.


JD

Assuming the sim is accurate, 2600 ft/s/s divided by 32.2 ft/s/s (gravity) = about 80.7 G's that the rocket will pull. For that reason I'd go with the 250G single axis.

It's a close call. The accelerometers on the 70G Ravens don't max out until somewhat above their max spec range, so 78-83 Gs is o.k. Those accels can be calibrated more accurately by the +/- 1G calibration routine than the 250G units can, so I generally recommend the 70G units unless you know you're going over 80 Gs. In my experience, motors tend to burn longer rather than shorter, so it really comes down to whether you're really going to build it as light, or lighter, than your sim. If it comes out a little heavier, I'd go for the 70G unit. Even if you rail out the accelerometer, you'll still have a good apogee deployment with the baro-based apogee detection; you just won't have data on exactly what your peak Gs and velocity were.

-Adrian