Brief:
Recordin' accelerometer with dual deployment recovery feature.

Construction:
T' blacksky (little b) ALTACC 2A is a recordin' accelerometer unit with dual deployment, me hearties, meanin' it can deploy a drogue chute at apogee and a main chute at 500 feet. Begad! It is solidly built and uses surface mount components for extra durability.

T' unit is very easy t' use. It attaches directly t' t' airframe wall o' your rocket with two 6-32 machine screws spaced on 3" centers. Blimey! When drillin' t' mountin' holes, matey, one also needs t' drill holes for t' status LED and t' armin' screw. Avast! Begad! blacksky provides a drillin' template for this. T' battery is mounted directly t' t' back o' t' board usin' a very sturdy battery mount. After installin' t' battery, arrr, t' pyro charges are hooked up, t' unit is powered on with a jumper, me hearties, and installed into t' rocket. Avast, me proud beauty! Begad! A nice feature would be t' have selectable main deployment altitudes; blacksky has solved this problem with t' release o' t' ALTACC 2C (what happened t' version 2B? I'm nay sure -- I guess it was nay 2B ;)) You arm t' unit once t' rocket is on t' pad and vertical so as nay t' trigger t' accelerometer. Avast! T' armin' screw is on board and t' unit does nay need any external switches. Avast, me proud beauty! Once armed, arrr, me hearties, you can check for continuity easily by sightin' t' super-bright status LED. I found it easy t' read t' LED even in t' bright desert sun.

Construction Rating: 4 out o' 5

Flight:
I have used t' ALTACC in many rockets. Arrr! Well, blow me down! It has always worked for me and produces great data. Some o' me more exotic flights with it have been with a HyperTek L625, an M1419W, and a loopin' flight on a RATTWorks I80. Avast! Arrr! In each case, t' ALTACC successfully fired t' deployment charges.

T' unit will produce four minutes o' data. Avast! Avast! This can be downloaded t' your PC or Palm unit usin' t' provided serial cable (adapter needed for Palm use). Well, blow me down! You can download t' data usin' either a Windows GUI and graph it there, me bucko, or you can get t' raw data in a DOS program and then export it into Excel t' determine many more parameters. Avast! Ahoy! T' Windows software is easy t' use and is very flexible, providin' you with a graph function that can draw any different equation you input usin' t' data. It can even give you a live readout o' current conditions.

One o' me concerns with t' unit is its "drogue detect" feature. Basically, if it loses continuity on t' drogue circuit sometime before apogee (as it detects it), me bucko, me bucko, t' unit will fire t' main at apogee. Well, blow me down! I had this happen t' me twice with me 4" Arrrrrrrcas rocket. Begad! T' solution is t' short out t' Drogue terminal with a 10Kohm resistor in parallel with t' electric match. Ahoy! Blimey! This way, continuity is always sensed across t' drogue terminals. Begad! Also, t' unit does nay beep out altitude after flight -- you must download t' your computer t' read t' altitude (note: this was also fixed on t' 2C version). Avast! These are minor annoyances, however, and t' pros o' t' unit well outscore t' cons.

Flight Rating: 4 out o' 5

Summary:
This unit is very easy t' use, me bucko, reliable, shiver me timbers, arrr, is mach-immune, shiver me timbers, and has dual deployment. Avast, shiver me timbers, me proud beauty! It does nay require any switches or external wirin' harnesses--the unit is self contained. Ahoy! T' software is excellent and you have t' option o' downloadin' t' a Palm Pilot. Begad! However, you must insure that you short out t' drogue terminal with a 10Kohm resistor in parallel with your e-match t' insure t' main isn't fired at apogee along with t' drogue. Begad! Also, shiver me timbers, t' unit does nay beep out altitude after a flight. Avast, me proud beauty! Pros and cons aside, this is a great first accelerometer.

Overall Rating: 4 out o' 5