Setting up MissileWorks RRC3 for staging

So I am setting up a MissileWorks RRC3 to ignite the sustainer on my Widman two-stager. Using the LCD, I have set the Auxiliary Comparator Operation to 2 (Alt >= ACV x 100). The Auxiliary Comparator Value (ACV) is set to 15, which should be 1,500 feet (15 x 100). However, in the lower right hand corner of the LCD display, it shows a little "x 10". This would mean 150 feet. So is the manual correct at ACV x 100, or the LCD correct at x 10? I am currently using what the manual says, but this is making me nervous for my first HP two-stager.

Hi Dale -

The x10 indicator is for adjustment purposes (the CV can be set to 999 max, and the x10 adjuster lets you multiply the current value times ten vs. clicking the up button 999 times)... your value of 15 does represent a comparator value of 1500' AGL using the comparator operation chosen (Alt >= ACV x 100).

Here's a sample 2000' permissive, 3 seconds after launch (from the User Manual):

Aux Output Control Sequence (OCS) Event -> Timer -> 1-Shot Compare
Auxiliary Trigger Event Launch
Auxiliary Comparator Operation Alt => ACV x 100
Auxiliary Comparator Value (ACV) 20 (2000 ft)
Auxiliary Timer Interval 30 (3.0 seconds)
Auxiliary Output Control Value 1 (1-Shot)

Jim,

I appreciate the quick reply. Looking forward to trying this tomorrow.

Dale

I don't mean to hijack this thread but it appears that the instructions don't jive with the mdacs software regarding the aux timer units. Instructions say timer is set in tenths, software asks for seconds. I nearly set mine 10 times longer than I wanted it. I only caught it at the last minute because I printed out the setting sheet.

Is that correct? For a 6.0 second delay, I would set it at 6.0 in mdacs, not 60?

I used the RRC3 yesterday for sustainer ignition. I set the Auxiliary Timer Interval to 45, which was 4.5 secs. It worked as planned, the booster recovery was a different story...

DEmery said:

I used the RRC3 yesterday for sustainer ignition. I set the Auxiliary Timer Interval to 45, which was 4.5 secs. It worked as planned, the booster recovery was a different story...

Click to expand...

What happened to the booster?

The parachute did not deploy, and it came in ballistic. We heard its death scream, but never saw it. I did not find the wreckage, so I do not know what failed.

Hmmm. Sorry to hear. So the dumb question would be did you not have motor ejection as backup for the booster?

No, I do not use motor ejection for backup. It is hard to determine a delay time. If the booster had drag separated (it did not) you can make a reasonably good guess, but I expected the electronics and recovery system to work. I ground tested it and it worked fine. I am guessing the chute did not exit the body tube, but I really don't know. Stuff happens sometimes despite our best efforts. Expensive stuff sometimes. But it was fun, and I think I will try it again.

Dale

The flight was spectacular. Here's a video from Dale's on-board camera.
https://www.facebook.com/groups/BigSkyRocketry/permalink/614407265406929/



[emoji1010] Steve Shannon [emoji1010]

After watching that video, it looks like you never got booster separation until the sustainer motor ignited.

Yes, it did not drag separate. I am wondering if the motor damaged the electronics compartment.

Dale

Binder Design said:

I don't mean to hijack this thread but it appears that the instructions don't jive with the mdacs software regarding the aux timer units. Instructions say timer is set in tenths, software asks for seconds. I nearly set mine 10 times longer than I wanted it. I only caught it at the last minute because I printed out the setting sheet.

Is that correct? For a 6.0 second delay, I would set it at 6.0 in mdacs, not 60?

Click to expand...

Mike -

I just reviewed this thread again after watching Dale's staging video and noticed your question.

When entering/editing data using the LCD Terminal, you are dealing with "raw" values (no UI). Thus, you are correct, when entering the Aux Timer value via LCD, it is expressed as 0.1 second increment.

The mDACS Settings Manager does an implicit x10 translation and multiplication for the Aux Timer value. It is labeled as seconds and provides 0.1 second resolution (1.0 seconds = Aux Timer value of 10). Likewise in the mDACS Settings Manager, Aux OCS settings have enumerated text vs. the raw numbers you'd see when using the LCD.