Finding your rocket in a corn field

[andrewsaccounting]

I recently was introduced to HPR and made the Level 1 certification. On that launch, the rocket while it didn't go super high, it still managed to drift into a corn field, a tall one. While luckily the rocket was recovered, it was rather daunting. Are there non-gps ways to make zeroing on the location options? I am likely not to have a payload bay. Just seeing if there are some options that will make my feet appreciate the effort.
Thanks
Andrew

 

[downhill_D]

I have used a cell phone compass before. Although not the best, if you start with at least a line of sight to match to degrees on your compass you can walk right to it, as long as you hold a straight line from your start point. I hold my phone in line with the main chute and use that compass reference (mine shows in degrees). There are also small noise makers you can buy that have lasted some folks here more than a days noise (and lights) on one battery. Enough noise for someone to track it down relatively quickly.

 

[mtnmanak]

Attach one of these on your shock cord so it pulls the pin when the chute deploys. It is very loud.

https://www.amazon.com/gp/product/B07DMT8SLQ

 

[dhbarr]

Beepers and/or flashers are the simplest.

 

[Titan II]

Something to consider regarding the personal alarms. If there is a chance your rocket may end up on a phone line/electric line/tree/etc. in a residential neighborhood, it is not really a good idea.

 

[sl98]

I am likely not to have a payload bay.

You don't need a payload bay to use a mini Eggfinder GPS. There are shock cord mounting bays that you buy or easily make yourself. I have one shock cord bay that is made from 24mm body tube and bottle cap lid. I have another made from a 55mm coupler and gallon milk jug lid. Both are used with a mini Eggfinder. The rocket in the pictures below utilize the 24mm shock cord bay. I can tell you from experience that GPS is the best way to find a rocket in corn.

 

[boatgeek]

Something to consider regarding the personal alarms. If there is a chance your rocket may end up on a phone line/electric line/tree/etc. in a residential neighborhood, it is not really a good idea.

A well-proven corollary to Murphy’s Law: a rocket with a screamer will be inexorably attracted to power lines.

 

[caveduck]

Specific to corn (former Midwesterner here): You can't see across the rows much at all, but you can often see a surprising distance *along* the rows. So if you have a general line on the area where it landed, it's best to carefully travers the rows crosswise (be nice to the farmers, go through gaps and try not to knock down any plants) while looking in both directions along the rows. The main tricky part is knowing how far into the corn it went. Large rockets can be a lot more distant than they seemed, especially if you watched the landing with binoculars. Also be aware that smaller rockets can easily drape themselves across the tops of the rows and be hard to see even if you get very close.

The modern solution is to get a drone up over the area and look for the parachute...beepers run down. Once you get to L2 rockets, the value of the airframe / motor casing / parachutes / altimeters gets to the point where an Eggfinder GPS tracker is really worthwhile insurance.

 

[OzHybrid]

Get a laser pointer on a tripod. Get someone to follow the rocket down and lock off the laser which now points to your rocket. That gives you an exact line to walk to the rocket
If you can find 2 people/lasers/tripods, you can triangulate the position of the rocket. Don't use a laser that will damage your eyesight.
Or use 2 really powerful CO2 lasers and the spot in the field that bursts into fire........ no....no......just the first method. Works well.

 

[PhilC]

1. Rape alarms give an audible signal which is useful for homing in on the rocket if you know roughly where it landed.
2. Take a compass bearing, draw it on the map as a pencil line and walk the line. Better still have two or three people take bearings from different points and triangulate.
3. If you don't want to lose the rocket, don't press the button.

 

[trialsguy]

Attach one of these on your shock cord so it pulls the pin when the chute deploys. It is very loud.

https://www.amazon.com/gp/product/B07DMT8SLQ

Will the alarm fit in a BT-55 tubed (1.35” diameter) rocket? Will it work if the outer case is removed and replaced with heat shrink to make it smaller?

 

[Tractionengines]

We use a $15 ViFly Beacon (self contained and self powered lost drone beeper). It's small and light enough to fly in down to BT-50 size If not for the 105+db beeper, would not of even looked for a 1" dia 20" long rocket in a 100 acre corn field.

We did have a good line on direction. So my son (his rocket) and I went for a walk. When stopped and listening, we could hear it about 150-200 feet away. It was actually hanging in a small opening, which may have helped sound travel.

Here is website. Program is not optimized for rocket use. But works well enough. It's loud (without being too annoying if you hang it in a tree.) and will flash a very bright Blue LED if in a dark area, or at night.
https://www.viflydrone.com/viflybeacon.html

 

[neil_w]

I like that they advertise it as "wireless". My first reaction was "as opposed to what, an ethernet connection?"

 

[mtnmanak]

I like that they advertise it as "wireless". My first reaction was "as opposed to what, an ethernet connection?"

Come on Neil, you haven't heard of "fly-by-wire"? It's all the rage these days.

 

[FlyBy01]

I recently was introduced to HPR and made the Level 1 certification. On that launch, the rocket while it didn't go super high, it still managed to drift into a corn field, a tall one. While luckily the rocket was recovered, it was rather daunting. Are there non-gps ways to make zeroing on the location options? I am likely not to have a payload bay. Just seeing if there are some options that will make my feet appreciate the effort.
Thanks
Andrew

A bit more on the expensive side is a GPS tracker such as the Featherweight GPS tracker. Love mine.

 

[Tractionengines]

I like that they advertise it as "wireless". My first reaction was "as opposed to what, an ethernet connection?"

LOL... different world...

Their Finder and Finder2 connect to the Drone, or R/C Plane, flight control, and battery connections. They stay at full charge from the main battery. If the power supply connection is broke it triggers alarm mode from the internal battery. Or the controller can trigger alarm mode. Or the pilot can trigger alarm mode. Lots of "wired" options.

This version (Beacon) is "stand alone" for smaller, simpler Drones, and "other uses" where a control system is not available.

 

[mtnmanak]

Will the alarm fit in a BT-55 tubed (1.35” diameter) rocket? Will it work if the outer case is removed and replaced with heat shrink to make it smaller?

Unfortunately, this one won't fit in a BT-55. Pictures below - with the pin in, they are about 1.9" wide and the body itself is about 1.6" wide.
I don't think you can shrink it much by taking out the internals. Maybe you could shrink it down an 1/8", but that still isn't going to get it small enough for a BT-55.

Also, note that I remove the crappy keychain these things come with (they rip off with no effort at all) and drill a small hole through the top and install a kevlar thread loop. As you can see in the photo of the internals, you have to be careful not to drill through the speaker, but the kevlar thread will not break.

Finally, I have tried some of the beepers made for rockets and drones that have the 105 dB sirens. These turned out to be too weak for me to hear when the rocket fell inside relatively dense foliage, such as soy beans. These beepers are 145 dB and are much louder. Remember, dB's increase on a logarithmic scale, so an increase in 40 dB isn't a 50% increase, it is about 20 times louder. These things hurt your brain.

 

[Tractionengines]

Yes GPS is great but 3 issues:
1) Size/weight.
The systems are getting smaller all the time, but they still need decent sized batteries.
2) Cost
All GPS systems are a lot more than beeper and flashers.
3) The last few feet. (Here is where I like beepers most.)
GPS Will get you within 10-20 feet fairly quickly. But in a mature corn field, or under the leaves of mature soybeans you still have searching to do. If its beeping, you can hone in on that last little bit a lot easier.

For less than 6 grams, under $20 and battery lasts over 30 hrs. I fly the beeper in almost everything they will fit in. Helps speed the recovery, and not so annoying that if you hang it in a tree the neighbors kick you off the launch site.

 

[waltr]

Lots of methods for corn field searches.
When the corn is over chest high at our local field we tend to have about half the number of flights. This is due to everyone heading into the corn for the search. Many good suggestions in posts above.
Many of us don't fly smaller rockets when the corn gets tall, harder to see and harder to put beepers, beacons, etc into the rocket.

Beeper/buzzers are helpful but they MUST be beeping. I've seen a few stop upon landing due to battery connections, etc.

I use a small RF (Ham radio) beacon and RDF to find my rockets. This works well at limited range of about 50 feet. I've never had a problem getting close enough to pick up the beacon.

Another method with only a few people is:
Get a line on where the rocket went into the corn. This person DOES NOT MOVE and keeps something in the background, Tree, building, etc in sight. Then the searchers go out and with Cell Phones the person fixed at the launch keeps them on the line directly to the rocket. Works best with two people going out and staying about 10 feet apart on each side to the 'line'.
Three of us launched near a huge corn filed last year. When we didn't have a good line to follow the rockets were never found (two went over a hill and we could not see where they went into the corn). When we had a line and used this method recovery was successful.

Rockets can hide easily to corn and many times one needs to be within a few feet to see it.

 

[teepot]

I have a Marco Polo. Works well. I just got an Eggfinder GPS set up.

 

[rhoward99]

I second the Marco Polo. I own one and have found rockets using it. It's really easy to use. You just secure the transmitter to your shock cord, and it will wait patiently in idle mode (for a very long time before the onboard battery runs out) until it is pinged by the transceiver on the ground. Once pinged, it will start transmitting to the ground unit, which has an arrow that points in the direction of the transmitter. Very easy to use, and works very well. There is anecdotal evidence (https://www.rocketryforum.com/threads/marco-polo-tracker-great-bang-for-the-buck.160840/) that it works well in corn fields. I recommend the advanced drone system, as it is more robust the the system for pets.

https://eurekaproducts.com/advanced-drone-category/
You can find them on Amazon as well.

Regards,
Rick

 

[Rocketclar]

What I've done is use a handheld Garmin to project a waypoint. Then I have the unit record my track so I can see where I've been and where I am relative to the line. That's worked well for me at times.....getting a good sighting is important.
At our club we also have a spotter on a cell phone give directions to the person out in the field via cell phone. The one in the field holds up a pole so that the spotter can direct them to the line.
In one case, the only way I found my rocket in mature corn though was with an Eggfinder GPS system.
I've used audio sirens but they seem to always quit on landing.

 

[MidOH]

-Tie some cookies to an old engine. Toss past your dog into the woods.
-Take doggo to rocket launches.
-?????????
-Profit!

 

[trialsguy]

We use a $15 ViFly Beacon (self contained and self powered lost drone beeper). It's small and light enough to fly in down to BT-50 size If not for the 105+db beeper, would not of even looked for a 1" dia 20" long rocket in a 100 acre corn field.

We did have a good line on direction. So my son (his rocket) and I went for a walk. When stopped and listening, we could hear it about 150-200 feet away. It was actually hanging in a small opening, which may have helped sound travel.

Here is website. Program is not optimized for rocket use. But works well enough. It's loud (without being too annoying if you hang it in a tree.) and will flash a very bright Blue LED if in a dark area, or at night.
https://www.viflydrone.com/viflybeacon.html

How do you activate the the beacon in a model rocket? I don't see a "pull pin" anywhere on this unit? Do you just push the "on" button before launching?

I see that they sell an even smaller one, at 2.7 grams.

Thanks.

 

[Tractionengines]

Yep...Turn it on just before launch. If it's completely still too long it will start its no activity chirp. If set to highest sensitivity, it may detect launch as crash and go into alarm.

Otherwise, once rocket stops moving "on the ground" it will start its alarm progression process. (or) if its in a tree and still moving, then it may take 40 min to start alarm progression. ( It's programming says if a flight is over 40min something is wrong...)

Not IDEAL program, but good enough, and has helped us find even small rockets.

For the cost, size, weight, volume, light, and battery life... I like it.

 

[Hobie1dog]

We use a $15 ViFly Beacon (self contained and self powered lost drone beeper). It's small and light enough to fly in down to BT-50 size If not for the 105+db beeper, would not of even looked for a 1" dia 20" long rocket in a 100 acre corn field.

We did have a good line on direction. So my son (his rocket) and I went for a walk. When stopped and listening, we could hear it about 150-200 feet away. It was actually hanging in a small opening, which may have helped sound travel.

Here is website. Program is not optimized for rocket use. But works well enough. It's loud (without being too annoying if you hang it in a tree.) and will flash a very bright Blue LED if in a dark area, or at night.
https://www.viflydrone.com/viflybeacon.html

that one is not loud enough for me to hear. when the guy in the video got back 50 meters he started having trouble hearing it.

 

[Hobie1dog]

Specific to corn (former Midwesterner here): You can't see across the rows much at all, but you can often see a surprising distance *along* the rows. So if you have a general line on the area where it landed, it's best to carefully travers the rows crosswise (be nice to the farmers, go through gaps and try not to knock down any plants) while looking in both directions along the rows. The main tricky part is knowing how far into the corn it went. Large rockets can be a lot more distant than they seemed, especially if you watched the landing with binoculars. Also be aware that smaller rockets can easily drape themselves across the tops of the rows and be hard to see even if you get very close.

The modern solution is to get a drone up over the area and look for the parachute...beepers run down. Once you get to L2 rockets, the value of the airframe / motor casing / parachutes / altimeters gets to the point where an Eggfinder GPS tracker is really worthwhile insurance.

At the NSL my rocket wasn't found even using a high dollar drone.

 

[FMarvinS]

Mtmanak-I like the beepers you suggested (decibels ad price). Since the pull-pin is on the beeper's side, 90degrees from the "pull" direction of the shock cord/chute, does this cause damage to the beeper on chute deployment. If not, please specify placement in rocket.

Thanks,
Fred

 

[ep29030]

I used to get a line on it, then have one person look at the line, and the retriever held a stick in the air with a piece of cloth on the end. Then you could shout "left","right" as they walked. Always worked for us. Also, add a long streamer to recovery train to increase your chances of seeing the rocket.

 

[mtnmanak]

Mtmanak-I like the beepers you suggested (decibels ad price). Since the pull-pin is on the beeper's side, 90degrees from the "pull" direction of the shock cord/chute, does this cause damage to the beeper on chute deployment. If not, please specify placement in rocket.

Thanks,
Fred

Fred - that is a good question. As shown in the photo below, I have been using zip ties to attach the siren to the shock cord between the parachute, ensuring the length of shock cord is longer than the length of the siren cords. Then I wrap it all up in a Nomex blanket. When the main laundry is deployed, the shock cord stretches out and pulls the pin. Thus far, I have not encountered an issue with the pin being on the side of the device - it has always pulled out cleanly for me. The only issues I have had are either with the keychain (as noted in the post below) or ground issues. Last week at a launch, the siren laid down nicely and perfectly in an irrigation ditch filled with water. Unfortunately, the siren is no longer functional.

Having said that, looking at the picture of the internals in the post above, it may be possible to drill the hole on the side of the unit just above the batteries. I have a couple that need to be drilled and threaded before the next launch, I will try that and report back if it works well.

One of the best features of these particular screamers is that they are cheap. At just under $4 a pop (including the kevlar thread and zip ties), they aren't disposable, but, if one gets lost or broken, I am a lot less heartbroken than losing one of the $20+ models I have seen sold for rockets and drones (which also aren't as loud). I understand these aren't a great solution for smaller diameter rockets, but for most HPRs and some MPRs, this is stupendously cheap insurance. I use them in addition to all my GPS and RF electronics.