Missile Works introduces the RRC2+ / Dual-Event Altimeter for $45

[dixontj93060]

I had to order a couple to try out. They will go well in my future expansion into EX.

My CATO per launch ratio is much worse for commercial than it is for research. Still I ordered two as a matter of convenience given I have so many RRC2mini slots in my fleet.

 

[thobin]

Hey how about some pictures of the back side?


TA

 

[Viperfixr]

This is perfect for my next build, a dual deployment Wildman Wild Child (38mm airframe). If I was going to use a LiPo battery due to space concerns in the 38mm coupler av-bay, what battery would be within the limits of the altimeter? How about something like this one (7.4V 500mAh 10C Li-Poly Lipo Battery Pack)?

 

[CarVac]

This is perfect for my next build, a dual deployment Wildman Wild Child (38mm airframe). If I was going to use a LiPo battery due to space concerns in the 38mm coupler av-bay, what battery would be within the limits of the altimeter? How about something like this one (7.4V 500mAh 10C Li-Poly Lipo Battery Pack)?

That would be easily overkill, I'm sure.

 

[dixontj93060]

This is perfect for my next build, a dual deployment Wildman Wild Child (38mm airframe). If I was going to use a LiPo battery due to space concerns in the 38mm coupler av-bay, what battery would be within the limits of the altimeter? How about something like this one (7.4V 500mAh 10C Li-Poly Lipo Battery Pack)?

No. Too much battery for the RRC2+. Get the smallest mAh 3.7V LiPo you can find.

 

[o1d_dude]

Definitely a "buy it and fly it" proposition.

I like it!

 

[Viperfixr]

No. Too much battery for the RRC2+. Get the smallest mAh 3.7V LiPo you can find.

I looked up the RRC3 manual for max battery output amps, and it says 5 amps are what the outputs are rated for. Correct me if I am wrong, but I think even the tiny Raven 3.7V LiPo will exceed that! Doesn't sound like a Lipo is a good option with this altimeter.

I sure like this altimeter, however. CJ showed me a beta he took to BALLS recently--small, easy and effective altimeter--love it. So, I need to find a way to make a 9V fit into a 38mm airframe without a lot of trouble.

 

[dixontj93060]

I looked up the RRC3 manual for max battery output amps, and it says 5 amps are what the outputs are rated for. Correct me if I am wrong, but I think even the tiny Raven 3.7V LiPo will exceed that! Doesn't sound like a Lipo is a good option with this altimeter.

I sure like this altimeter, however. CJ showed me a beta he took to BALLS recently--small, easy and effective altimeter--love it. So, I need to find a way to make a 9V fit into a 38mm airframe without a lot of trouble.

You have to find the lowest mAh and C rating combination possible. You can still find 120mAh 8C and 10C batteries which in turn deliver 1A to 1.2A which are fine under normal operation given the impedance and duration of an e-match burn. Where you run into problems, as Adrian A. has pointed out, is when your are lighting a motor and you get a plasma effect in the chamber leading to a longer duration direct short. So in the case of staging or airstarts I would then move to a 9V setup.

 

[Binder Design]

Where you run into problems, as Adrian A. a has pointed out, is when your are lighting a motor and you get a plasma effect in the chamber leading to a longer duration direct short.

I think that is what erased the firmware in my parrot. I was doing head end ignition of a motor so the match was exposed to the motor burn. Toasted that alt on the first flight.

 

[jd2cylman]

Credit card just bit me for working it too hard. Two RRC2+ alts on the way to Malta. It's only money, right? Just means retirement will have to wait another year. :eyeroll: Lets see, I think that makes my retirement age 85ish

Adrian

 

[etoyoc]

I am glad to see these coming out. I will be ordering one soon (may even fly on my L2 attempt if I can get it soon enough) Are there enough differences between this and the RRC2 Rev C. to make this a good pair for redundant altimeters or should I pair this with something with a greater difference in design?

 

[dixontj93060]

I am glad to see these coming out. I will be ordering one soon (may even fly on my L2 attempt if I can get it soon enough) Are there enough differences between this and the RRC2 Rev C. to make this a good pair for redundant altimeters or should I pair this with something with a greater difference in design?

Jim should probably answer, but I'd guess quite a bit of difference from RRC2 since the RRC2+ is a derivative of the RRC3 platform.

 

[MWC]

When it comes to the subject redundant altimeters, there are several definitions that folks apply... one of these definitions has classically been the use of "differing" manufacturers. The reasoning is to provide different alogrithmic implementations, and perhaps even different sensing technologies. If you really want redundant systems, I could see using a baro-sensor system and an inertial-sensor system in tandem. Perhaps there's a third fail-safe timing system even, but I digress.

The RRC2 Rev. C platform and the RRC2+ in tandem would be fine if you do want two units... they differ significantly in componentry and implementation, but perform the same core barometric based deployment duties. The biggest operational difference between them is the mach-immunity feature of the RRC2+ vs. the RRC2 Rev. C platform.

It all comes down to your personal prefereneces and comfort factor... I can't tell how how many flyers have flown dual Missile Works RRC "flavors" over the years for sport or certs, but it has been a large number of flyers.

 

[jd2cylman]

I just got two of the RRC3's last week from Tim, and two of the RRC2+'s from MWC yesterday. My plan is to pair up a RRC3 with a RRC2+.

Adrian

 

[MWC]

Hey how about some pictures of the back side?


TA

Here's a quick back side pic from a production panel... First wave of orders will be flashed tomorrow, then I'll spray and bake... final bed-of-nails test is next, then bagging and shipping. We're on-track to ship RRC2+ orders on the 21st.

 

[Viperfixr]

No. Too much battery for the RRC2+. Get the smallest mAh 3.7V LiPo you can find.

How about this battery? With 250mAh and a 20C rating, it should only put out 5 Amps in max discharge, right?

 

[dixontj93060]

How about this battery? With 250mAh and a 20C rating, it should only put out 5 Amps in max discharge, right?

Well yes, but I wouldn't use it. Again, your best bet for alt survival is the lowest mAh, lowest C and lowest voltage (that is still compatible with the alt) combo you can find. During beta test of the RRC2+ I used 120 mAh, 10C, 3.7V (4.2V operating) LiPos on two of the flights--these work great and I will continue to use them.

 

[CarVac]

How about this battery? With 250mAh and a 20C rating, it should only put out 5 Amps in max discharge, right?

The C rating has little to do with the internal resistance of the battery. If shorted, such as in the case that the igniter/ematch is engulfed in a conductive flame plasma, it will happily deliver current exceeding its C rating.

 

[dixontj93060]

The C rating has little to do with the internal resistance of the battery. If shorted, such as in the case that the igniter/ematch is engulfed in a conductive flame plasma, it will happily deliver current exceeding its C rating.

Correct as Adrian A. has pointed out, but it does apply in the case of normal ematch operation outside of a motor chamber with a controlled, quick burn into the 1 to 3 ohms of the ematch load.

 

[etoyoc]

Just ordered one and if it is here on time, it will be flying paired with that RRC2 Rev C on my L2 attempt. Now, the question becomes if I want to get into LiPo batteries. I am finding a lot of cheap 1s LiPo, but not many that meet the 10C suggestion. So what are the big advantages of using a LiPo that is just above the operating voltage of the altimeter?

 

[CarVac]

Just ordered one and if it is here on time, it will be flying paired with that RRC2 Rev C on my L2 attempt. Now, the question becomes if I want to get into LiPo batteries. I am finding a lot of cheap 1s LiPo, but not many that meet the 10C suggestion. So what are the big advantages of using a LiPo that is just above the operating voltage of the altimeter?

Tiny, cheaper in the long run than 9-volt batteries.

 

[JMZawodny]

I was happy to see these come out and just ordered a few today. I'll probably pair these with the 1S 130mAh 10C LiPo cells I usually use with my Ravens. I have a few 38mm diameter projects these will be perfect for.

 

[tbrogan]

I think you meant to say "water OVER the bridge", or perhaps even "water THROUGH the bridge".

So long as they don't say, "What bridge?"

Nice looking and simple alt! That's the kind I love seeing I don't have a ton of time to keep up with them and programming and settings. I set my Hi-Alt45K and actually have only changed the settings once, after the first flight. From 800 feet main deploy to 400 feet main deploy. Been looking for a second and possibly a third, this may be the optimal choice.

T -

 

[MWC]

Thanks to everyone for your support... we're able to drive in/out to Estes Park on "odd" hours past all the construction and repair, so we can actually "drive" vs. walk". We're shipping the first wave of RRC2+ orders today, and we'll have all the other backlogged RRC2+ orders packed this weekend for mail-out early next week.

 

[dixontj93060]

Got my shipping notice and it looks like my two RRC2+'s will be in my PO box with time to spare for use at MWP11 :w:

Thanks Jim!

 

[jlnel]

just a lil bookmarkie to come back to. looks great.

 

[cwbullet]

I received a nice package. The altimeter is smaller than I thought.

 

[gdjsky01]

Order placed.

- jeff

 

[MWC]

Update -

All remaining RRC2+ orders are now fulfilled and packed for shipment tomorrow.
Thanks again to everyone.

 

[fyrwrxz]

Update -

All remaining RRC2+ orders are now fulfilled and packed for shipment tomorrow.
Thanks again to everyone.

Jim- Just for my (and everyone else) edification-is a 3.7 250Mah/25C too much? It's the smallest I have on hand.