Altimeter? No altimeter?

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On my last parts order, I considered adding an altimeter. I didn't because I've already spent more this month than I should.
On the one hand, if accurate, it could give me some useful data that would help me choose motors and tell me what direction my builds should take.
On the other hand, rather than placing some importance on aesthetics and just enjoying watching my rockets fly, I'll be fixating on how high they went.
I assume most of you serious rocketeers use an altimeter, or is that a false assumption?
 
Until recently, I only ever used an altimeter when I needed electronic parachute deployment. I just fly for fun and to see if a thing works, so I never bothered with electronics in little rockets because of perceived hassle with installing electronics. However, then I heard of Jolly Logic, whose products can simply be attached to the nose eyelet with a key ring, and then bought an AltimeterThree right before COVID prevented me from using it. I'm mostly planning to collect data on flights out of curiosity though and still have no intention of fixating a lot on it. As long as it works, it's a success to me.
 
If you get an altimeter, get the right one for your needs. As a low power flyer you don't need dual deploy capabilities. What do you want to measure? Just altitude, or is other data interesting to you? Do you want data throughout the flight or just the max values?

Look at Perfectflite if you want continuous altitude data. However, you need a dedicated av bay for this. Well made, works well, easy to use and a reasonable price. I have the Pnut and use it regularly in some of my rockets with av bays. Altitude data is provided with beeps, but the full data can be downloaded later with a special cable available from Perfectflite.

Jolly Logic is probably your other option. Very well made, works well, very easy to use and several options to choose from. The Altimeters One and Two only record peak values with the Two recording 10 different values. Data is provided by a small LCD screen. I have the Two and really like it. The Altimeter Three synchs to your phone and provides continuous data for a number of values. No av bay needed, so pretty much any rocket that these fit can have data. Not cheap, but you are paying for quality and ease of use.

The Estes altimeter. As they say, if you can't say something nice don't say anything at all. If I could find mine I would send it to for the cost of postage (and feel bad for charging you that much).
 
I use altimeters in all my rockets. I was slow to start using them because motor ejection just seems easier, but once you get started they just become part of the build.
 
I fly a JL Altimeter 3 in a subset of my rockets, sometimes, just for fun and interest. It's not in any way a necessity in low powered rockets. I do like to use it to calibrate my OR models with actual flight data.
 
I have a few altimeters. I have the JL Alt II and love it: small, simple, easy to attach & use.

But, having said that, you will be adding weigh to your rocket, so you will loose altitude. it wont' fit into small tubes, and there is the potential that it will get lost or fowl the chute / recovery device. (had both happen)

Sometimes, it will go off on the pad, and you loose your flight data (a knock when loading on the pad might trigger a false start, a long delay might drain the batteries, or some other forgetful issue) Most of these are barometer based, so if you're flying on a day that has warm or cold front approaching, you will likely get different readings on the same rocket on the same motor, but at different times of the day, etc..) And, don't expect consistent readings. If you launch the same rocket on the same motors, and as quickly as you can, you can have readings that are all within 100' or so, but none will be an exact repeat. Too many factors to account for, so you'll need to work out what is your acceptable % error..

Some of us will have redundancy built in; using 2 or three altimeters to validate & control the flight. Even when 2 altimeters are side-by-side, in the same AV bay, we can see a difference in the collected data..

I find they are more to validate the sim, and to have some bragging rights..
 
Be aware that 'altimeter' is being used differently by different people.
If you'd just like graphs of the flight and recovery, the Jolly Logic Alt3 is probably unbeatable.
The JL Alt2 is pretty good - but it's a small screen and occasionally gives strange numbers due to bumps and jolts. The Alt3 has the whole graph.

Rocketeers also use 'altimeter' referring to flight computers/controllers of varying complexity. Flight controllers report back apogee, and may or may not record the whole flight. They also control electronic events for pyros, hot wires, or servos. Deployment, chute reefing, airstarts, stage/pod separation, all kinds of niftiness. Some will go down to 1" diameter rockets. Most are bigger.

My tip - get some practice in the field of your choice first. Get an idea of how likely you are to loose rockets to corn fields, trees, swamps, and other rocket recovery hazards. Altimeters are expensive - you'll want them back.
 
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Above all, of the few rules i have for flying:

"If you can't afford to loose it, you can't afford to fly it"

This, to me, applies here. I can't readily justify putting a $80 altimeter into a $20 rocket. I can very happily, lose a $20 rocket. Loosing an MPR, ~$100 rocket with a $60 case & $80 altimeter is a little more concerning..
 
I thought about getting one many times, but haven't gotten to it yet. Their costs have been rising faster than my interest.

The only altimeter I have is a dual-deployment chip and I've only used it once so far (successfully!). Aside from my long-term staging plans, I don't think it's in my future.
 
Define serious rocketeer? Which I'm sure I don't meet that qualification...yet. But my input here is that there are some guys that take LPR VERY serious and produce works of art. Then they take their chances with them at the flying field. I doubt many of them care about the altitude.
For high-flying HPR, and altimeter is pretty much a necessity as it's connected to a flight computer as part of a complex recovery system. Most of them are on the same circuit board with the computer. But do these guys also fly alts in their MPR and LPR rockets? That would be the question.
For me, if it's not going high enough for dual deployment, I'm more interested in watching it fly and the thrill of the hunt to get it back from the woods then I am about the numbers. I have a small field on my property to fly from at the moment (will be clearing more later on in prep for some animals), and my LPRs love pine trees.
Also, like other's said, the cost is more than my LPRs cost. I scratch build everything, even the kits that I bash, so my rockets cost next to nothing aside from a few niceties that I'm not bothered to make myself (chutes, nose cones, and sometimes centering rings). Even a $20 altimeter would triple the cost of my small builds, and that would be the rocket that decides to turn sideways about 50 ft up and head for the neighbor's forest.
 
Be aware that 'altimeter' is being used differently by different people.
If you'd just like graphs of the flight and recovery, the Jolly Logic Alt3 is probably unbeatable.
The JL Alt2 is pretty good - but it's a small screen and occasionally gives strange numbers due to bumps and jolts. The Alt3 has the whole graph.

Rocketeers also use 'altimeter' referring to flight computers/controllers of varying complexity. Flight controllers report back apogee, and may or may not record the whole flight. They also control electronic events for pyros, hot wires, or servos. Deployment, chute reefing, airstarts, stage/pod separation, all kinds of niftiness. Some will go down to 1" diameter rockets. Most are bigger.

My tip - get some practice in the field of your choice first. Get an idea of how likely you are to loose rockets to corn fields, trees, swamps, and other rocket recovery hazards. Altimeters are expensive - you'll want them back.
Losing one, first flight, would be a real drag. That is the best argument for not getting one I can think of.
Assuming I'd be launching at Pawnee Grasslands, losing one if probably low risk, until I start flying pretty high. There isn't much out there to hide a rocket. As long as I can see the chute deploy, I'll probably be OK.
 
Altimeters are one more step in the process of challenges in rocketry. A simple altimeter with deployment capability can not only deploy a single event but allow you to move on to dual deployment. In a single deploy setup you can add redundancy by retaining your motor eject. In a dual deploy setup you can fly higher and still recover your rocket.
If you have the ability to assemble it the Eggtimer Quark is a great buy at $20. It is probably the easiest kit to build that Cris offers. It will fit in a 24mm coupler or nose cone.
https://eggtimerrocketry.com/eggtimer-quark/
 
On my last parts order, I considered adding an altimeter. I didn't because I've already spent more this month than I should.
On the one hand, if accurate, it could give me some useful data that would help me choose motors and tell me what direction my builds should take.
On the other hand, rather than placing some importance on aesthetics and just enjoying watching my rockets fly, I'll be fixating on how high they went.
I assume most of you serious rocketeers use an altimeter, or is that a false assumption?

Flight Sketch is a very low cost option - I bought 2 for $40 I think + shipping. It is smaller than a 1/2 postage stamp downloads data onto an app. Works Great!
 
+1 for FlightSketch. Why aren't ALL flight computers Bluetooth capable. Just seems a no-brainer as opposed to listening/counting beeps.
Connect, Arm, Launch, Dump data all without opening the nose cone!
 

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Losing one, first flight, would be a real drag. That is the best argument for not getting one I can think of.
Assuming I'd be launching at Pawnee Grasslands, losing one if probably low risk, until I start flying pretty high. There isn't much out there to hide a rocket. As long as I can see the chute deploy, I'll probably be OK.
I've yet to lose one (for more than a day) at Pawnee, but it happens at every launch. I thought a brightly colored rocket with pink parachute would be fine. The spot it landed in was prairie in full bloom... took a while to find!
-Ken
 
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