When does a tracker become necessary

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viciouspeanut

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Morning everyone,

I am getting a little deeper into my motor choices and will be going DD soon so I will not be so scared of breaking 2k feet now. Question is, what altitude do you begin to think trackers are a good idea? I know it probably depends on fields and I intend to chat with the experts at mine Saturday, but I like to get lots of opinions.

Thanks!
 
Unless I fly under 2000 feet in a wide open field, I always use a tracking device!
 
If you can't see across the field and see it on the ground (corn, beans, trees) and/or goes high enough that you can't see it....you would benefit greatly from a tracker.
 
Well then.. I know our club uses Atlus Metrum but their products are a tad confusing so I'll try and get a look at some this weekend. I guess anything from them needs a HAM license
 
Every flight I do....if ya use one, ya never lose a rocket, needed or not. Don't use one, eventually ya will lose that rocket.

Even a little G-motor: Buddy & I were doing a drag race with Wildman minnies. I asked him where his tracker was? replied.. don't need it on low flight like this..

Button pushed, rocket whips to left.[never done that before after many, many flights].heads straight to the trees in a loooong low arc. Never to be seen again.

3 other times,over the years LCO pushes wrong button my rocket flies, after announcing someone else flight.
Had no idea where it went cause I wasn't looking.

Buy..Fly...Rocket comes home, be happy!
 
Agreed on the 2000’ especially 2” OD or below. As soon as motor burnout, hope u have a good smoke trail.

If hitting high speed, especially if it kicks off the rail.

Things to consider;
- sometimes they launch the wrong rocket and you were not even watching

- if there are crops / high grass or weeds

- upper winds can be very different. I saw my Mac Firestick barely heading east smoke trail at 10,000’ - winds were East to West! But upper winds were opposite, Rocket Found .8 mile EAST of launch pad with tracker, but everyone said there heard ejection charge WEST! Trust the tracker, I walked right to it.

- you spent a lot of effort building it

- I have $100 or more in it


Sent from my iPhone using Rocketry Forum
 
Well then.. I know our club uses Atlus Metrum but their products are a tad confusing so I'll try and get a look at some this weekend. I guess anything from them needs a HAM license


I have several of those units Telemega...Tele GPS they are easy to use but a bit pricey. 350.00 entry point , well worth it.
Several other 900 band, license free for 150-175 entry point [meaning both rocket tracking unit & ground receiver]

For simplicity RF tracking tape small unit on shock cord follow with ground unit

This is a must read for help with trackers, tons of info on using and buying:

https://www.rocketryforum.com/showt...w-to-use-them-that-dark-mystical-art-revealed!
 
Is there T-Mobile cell phone service at your field? If yes, you can get a GPS tracker for under $20, e.g., https://www.ebay.com/itm/K8-Multifu...ash=item3f8c1e90ea:g:Cr8AAOSwVqlaA~zR&vxp=mtr. If you have an old Android phone that fits your rocket, you can use it as a GPS tracker and altimeter with the free Insane Rockets app.

If no cell service, least expensive options I've seen are the Missileworks T3 for $150 and the Eggfinder ($100 kit, assembly required). I have the TeleMetrum and TeleBT from Altus Metrum, it's really great although more expensive.
 
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Lots of other people have written about ground conditions. Here's a middle aged guy with average (corrected) eyesight) view on visibility in the air.

4" rockets are pretty reliably visible to 5000 feet, 2" to 3000 feet. Take a thousand feet off for difficult sky conditions (haze, flat white overcast, etc.), not to mention whatever clouds there may be. You can maybe add a bit if you have good tracking smoke and a bright chute. If you go above that altitude, you'll want a tracker or you're just guessing as to where the rocket might land.

There are exceptions, but this is a pretty good rule of thumb. Also, don't launch a green rocket on a green chute into a cornfield and expect to find it easily. Colors not found in nature are your friend. If the vegetation is more than a foot high, consider a screamer as well to get you the last 25 feet to your rocket. I once stumbled across someone else's naked blue tube and fiberglass rocket that landed in sagebrush on a tan chute. It was invisible from 10 feet away unless you knew it was there.

I'm also a believer in hand-bearing compasses/phone compasses once you've seen the rocket land. Find the bearing it's on, and walk that bearing 10% further than you thought it could possibly have gone, and your rocket will be right there.
 
When does a tracker become necessary

I agree with everyone, I came through the same evolution,
but here in the northeast what happens when the Soy crops are mature ??
Then you can literally be standing on top of the rocket and not see it..
This is when you'll be told to use a tracker and a screamer..
The truth is,,
tracking is the next step in rocketry..
It's what your up to,, lol..
When you become proficient at tracking it will open up a whole new part of rocketry for you..
Flying as high as you dare on the field and knowing you'll find the rocket..

Don't shy away from tracking,, you're going there anyway..

Embrace it,, it's a lot of fun.. ( especially "Foxhunting" )..

Teddy
 
Tracking is a must have on anything you want to get back. I have watched two rockets of mine land in a field with crops and lost them.
 
Tube Size diameter of rocket, velocity and altitude go into my criteria. L-1 specific impulse MD airframes out of sight 3,000ft plus. Apogee deploy with 20-30mph winds aloft you are looking at a realistic 0.7-1.3 km wind drift into grassy, hills, or trees. On a salt flat have found 29Mm md from 5,000ft at 40 yards from pad. Anytime you are on a team competition with HPR the success is determined by returning mission payload which means finding it. Placed third nationally at SEDS with UTC on multistage L-1s. We used a HAM FCC dual GPS/APRS tracker because the FCC variants transmit over 400ft tall hills and through trees. Egg finder claimed expect to lose it near trees in manual. Altus metrum makes some fine products. Otherwise an egg finder beats nothing. Non FCC variants won't have selectable baud rates or the amount of data and precision during flight. Keep the G limits lower or your gonna lose a satellite lock. Radio beacons don't have a G lock limitation. The FCC variants are less toy like and have more features with live telemetry, voice callouts, and in flight data recording with live auto-save incase you implode some fancy prototype rocket with stuff you spent a lot of time designing. Depends on what you want really.
 
Everyone may have a different opinion.. For me , the time to invest in tracking has past. When I find myself out in the field , thinking I had a good "eyeball" on my rocket . And after an hour goes by and I am about to give up my search , I have the story in my mind on how to justify the loss / which I cant / .Then I finally hear that faint beeping from the altimeter. PURE LUCK...I say if your investment CANNOT be lost to something like not having a good eye on on the touchdown. OR you fly to out of sight altitudes.... Get the tracking , And for large , high altitude rockets , for safety..
 
For our competition scoring the booster was a write off kind of item. Found ours in a pond visually, lol. Granted most of the project wasn't paid by us. If someone scratch built something that took a lot of time or money they may want a tracker in a booster too at the expense of mass for finding it again. We were visually able to find boosters below 3k ft but it took a lot of eyes and walking. We heard horror stories of richer colleges trying to find rockets with airplanes and failing.

Write down coordinates and bearings as it comes in because that is a reference area incase the tracker looses lock before touch down. Terrain and obstacles can block RF signals of even the best devices. And if it's a real light rocket on WARP9 or VMAX forget trying to track the boost phase even with FCC regulated hardware, lol...that AIm Xtra has a better G loading than a TeleGPS. We found TeleGPS hated 168Gs.
 
Lots of other people have written about ground conditions. Here's a middle aged guy with average (corrected) eyesight) view on visibility in the air.

4" rockets are pretty reliably visible to 5000 feet, 2" to 3000 feet. Take a thousand feet off for difficult sky conditions (haze, flat white overcast, etc.), not to mention whatever clouds there may be. You can maybe add a bit if you have good tracking smoke and a bright chute. If you go above that altitude, you'll want a tracker or you're just guessing as to where the rocket might land.

There are exceptions, but this is a pretty good rule of thumb. Also, don't launch a green rocket on a green chute into a cornfield and expect to find it easily. Colors not found in nature are your friend. If the vegetation is more than a foot high, consider a screamer as well to get you the last 25 feet to your rocket. I once stumbled across someone else's naked blue tube and fiberglass rocket that landed in sagebrush on a tan chute. It was invisible from 10 feet away unless you knew it was there.

I'm also a believer in hand-bearing compasses/phone compasses once you've seen the rocket land. Find the bearing it's on, and walk that bearing 10% further than you thought it could possibly have gone, and your rocket will be right there.

Some Garmin handheld GPS units have a "Sight 'n Go" feature. If you see the descending rocket, you sight it on the unit, it can shoot a line in the direction where you are pointing it. Sure, it doesn't give you the range but it gives you a reliable
datum to follow. If you have to go around an obstruction it will still point you in the right direction. https://www8.garmin.com/manuals/webhelp/fenix5/EN-US/GUID-473708B3-200C-4ADF-BC13-2F1DC729B434.html

Several of their units have it. You have to look at the online instruction manuals carefully to see if the unit under consideration has the option.

I have not done this but I would think one could hold a Garmin Vista HCX or 60CsX (both of whom have Sight 'n Go feature) parallel to their Yagi beam and with the bearing locked in, as soon as there is loss of signal (LOS), hit the button on the Garmin and the bearing line is locked and gives you something to follow . This might be helpful with RDF tracking in the situation where the rocket is completely sight unseen liftoff to touchdown. The smaller the rocket the greater the chance it will be sight unseen even if it lands 1/2 mile away.

I usually have a Vista HcX hanging around my neck to take bearings off the cuff. Kurt
 
Wow, lots of responses! I fly mostly 3 and 4" rockets so I can usually see them, but as mentioned clouds can make that difficult at times. I actually have a SPOT that was given to me which would fit in my payload bays (I don't care about the weight penalty) but I'm not sure how well that would actually work. I am only concerned with finding stuff, not tracking the entire flight data. I guess I have to bite the bullet eventually. Our site is very flat, and has some building off to one side but is mostly clear (aside from trees on two sides). $350 is steep, but our club has an antenna and most of the members do too, and a "control trailer". If one was to go Atlus Metrum, which product is only the tracker (not altimeter combo)? Plus some seem to be GPS and RF? OR I could be misreading.
 
Worst case is you implode a rocket and visually find the GPS tracker on ground with battery disconnected from a super high G load. It depends on the terrain you fly at. So at worst the tracker is no guarantee. It has physical limits. We found the tracker by itself on a salt flat in Utah. We couldn't have seen in at Virginia in about a ft of twirling grassy weeds. The second flight we limited to 60.6Gs and the Altus metrum product did fine tracking boost phase. I don't know the upper limit between 60 and 168 G's.
 
TeleGPS, but seriously look at what your needs are first volume wise. There are better, but better costs more. It's worth the HAM license to have precision and range if you want to push 20,000ft or way higher.
 
I wish I had read about the ham handheld radios to use APRS in a direction distance measuring equipment capability. The handheld UV-5R will not do that as the more expensive units do.
 
TeleGPS, but seriously look at what your needs are first volume wise. There are better, but better costs more. It's worth the HAM license to have precision and range if you want to push 20,000ft or way higher.

The Tele-GPS is about the smallest APRS/GPS tracker available at this time. An EggFinder Mini is also small but I suspect the performance of the Tele-GPS on the 70cm band with a multi-element Yagi on the receive end would
out strip the 1/4 wave antenna on the EF mini on the 900Mhz ISM band. For sport flying in the Midwest, the Mini should be fine for finding stuff in grass and standing corn.

A potential for rocket finding is the 1 watt/500mW Sainsonic AP510: https://www.radioddity.com/sainsonic-ap510-aprs-tracker.html
Stick an AP510 in a 5-6: 1 Von Karman nosecone, set it for 144.800Mhz and one won't likely lose a large high flying rocket.

Only setbacks are the size of the unit with a 1/4 wave or 5/8 wave antenna, the fact it would never be usable for record attempts and the learning curve is high. Will record the positions to microSD card too.

One fellow posted here a year or so ago he loves flying his. Propagation on the 2 meter band would be an advantage out on the playa.

Just make sure the one watt signal doesn't dork the deployment electronics. I have messed around with them and they are impressive for the cost. Not for small rockets though. Kurt
 
Hi All,

I started using the Walston radio trackers years ago in Radio Control sailplanes. They saved a lot of planes over the years in our club. I use Vern Knowles GPS Multitronix “Kate” Tracker in all my 3” and larger rockets.

The Missile Works GPS Tracker System fits in a 54 mm rocket. I have this system but have not flown it yet. You cannot beat these GPS trackers. They take you right to the rocket even if it lands miles away. The “Kate” unit tells you exactly how far the rocket is from your current position.

Does anyone have a GPS tracker system that will fit in a 38 mm rocket?

All the best,
Bob
 
The Arrow antennas had a way to add external power if vehicle mounting to extend range of the receiving ground station communicating with the in flight GPS transceiver that communicates with the satellites. I think it would do light sub-orbital stuff no joke if externally powered ground station antenna, but that is beyond my experience level.

What I noticed what gets people is a maximum velocity tracking a system can do. You want a system that can handle the rocket performance. Some are optimized for weather balloons and have epic altitudes but do not do high velocity supersonic tracking. I think people have modified egg timers and other 900Mhz systems but once you get into HAM stuff it's literally plug and play at a higher price tag. My experience was only limited to TeleGPS and a 440-5 antenna. User support was awkward and the forum helped more than Altus, but good device once you got used to it.
 
TeleGPS fits in 29mm coupler tubes. We were doing 29mm MD work for comps. Hard to beat that capability. I'd love a 24mm coupler tube variant of a TeleGPS.
 
Hi All,

I started using the Walston radio trackers years ago in Radio Control sailplanes. They saved a lot of planes over the years in our club. I use Vern Knowles GPS Multitronix “Kate” Tracker in all my 3” and larger rockets.

The Missile Works GPS Tracker System fits in a 54 mm rocket. I have this system but have not flown it yet. You cannot beat these GPS trackers. They take you right to the rocket even if it lands miles away. The “Kate” unit tells you exactly how far the rocket is from your current position.

Does anyone have a GPS tracker system that will fit in a 38 mm rocket?

All the best,
Bob

Eggfinder, Eggfinder mini, Missileworks T3, and TeleGPS all fit in 38mm. The later 3 quite easily.
 
Does anyone have a GPS tracker system that will fit in a 38 mm rocket?


The new Missileworks T3 has a nice small footprint.

Entry price is 150 for a pair of base(Bluetooth) and rocket(GPS) units.
+your "tracking station" (I use my Android phone with Rocket Locator, others have recommended cheap a cheap android tablet)
 
I wouldn't have found this without a tracker. Note that no one could see it at all until it was almost down. Landed over 1000ft away in crops. Couldn't be seen until you were within 20ft.
[youtube]1wpPpMuxXyI[/youtube]
 
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