Chute Tamer - Good idea?

[uncle_vanya]

In another thread I ran across the "Chute Tamer" which Rockets By Melissa is selling for $200. https://shop.rocketsbymelissa.com/s...nid=BE0D107D5E82ED5799C17D795B1C5B46.qscweb21

This device kinda makes me uneasy. I was really excited when I first saw it then I read the user manual and realized it relies on a g-swtich and a timer for determining when to deploy. https://www.locprecision.com/site/loc/ChuteTamer/index.html & https://www.locprecision.com/site/loc/ChuteTamer/User%20Manual%20-%20CT4%20-%20R1.pdf

A while back I was trying to figure out a way to create a DIY version of the Aerotech Electronic Forward Closure using a timer - when I talked about doing Dual Deployment with a pair of timers or a dual event timer I was told this was a bad idea. After thinking it through I agree.

If the rocket doesn't travel vertically as high as predicted (wind, bad cd estimates, etc.) then the timer could result in a free fall to ground.

Thoughts?

EDITED to clarify the comments about the SIMPLE timer. It's a remarkable device in terms of deployment via fishing line etc. However the g-switch/timer method of determining when to deploy is what I am concerned about.

 

[fox_racing_guy]

I'll give you some user feedback here. The Timer is a Perfect Flight timer ( the Chute Tamer comes with the perfect flight owners manual as well) and the G switch is used to "start" the timer. No I won't sit here and tell you I'm a expert with the thing but I found it very easy to use just buy reading the extensive user manual.
I found it a easy way to convert a 2" rocket to dual deploy with out building a small altimeter bay and using a altimeter with E-matches and black powder. I do use altimeters in some of my larger rockets ( G-Wiz LCX & various Perfect Flight models) and to me this is just another "tool" at my disposal.

 

[cjl]

I don't think it's a very good idea, due to the difficulty in getting an accurate simmed descent rate. I would stick with a true altimeter for dual deployment.

 

[Dipstick]

I started flying dual deploy with a blacksky timer, simply because I could pay less for it (as a high school student). It took some very careful calculation of altitude, descent rate under drogue, weathercocking, and some fudge factor. I found that after some trial and error, I could get my rocket to dual deploy in the 400-600 region, but if there is any abnormality in the flight path, you're looking at a charge going off on the ground instead of at 500ft...:cry:

In my opinion/experience, pay a little more (now its not even that much) and go with the altimeter.

Bruce

 

[uncle_vanya]

I'll give you some user feedback here. The Timer is a Perfect Flight timer ( the Chute Tamer comes with the perfect flight owners manual as well) and the G switch is used to "start" the timer. No I won't sit here and tell you I'm a expert with the thing but I found it very easy to use just buy reading the extensive user manual.
I found it a easy way to convert a 2" rocket to dual deploy with out building a small altimeter bay and using a altimeter with E-matches and black powder. I do use altimeters in some of my larger rockets ( G-Wiz LCX & various Perfect Flight models) and to me this is just another "tool" at my disposal.

This sounds like a good idea - but how do you deal with flights with greater deviation from vertical than expected?

 

[TWRackers]

We need to convince them to design one with a built-in altimeter instead of a timer. Then I'd buy one in a flash.

 

[fox_racing_guy]

This sounds like a good idea - but how do you deal with flights with greater deviation from vertical than expected?

Lucky for me all flights so far have been straight as a laser beam so it hasn't been a problem. When I flew mine I deviated from the instructions buy looking at my motor delay (10 sec) and added another 5 seconds, this gave me a deployment time of 15 seconds. It still relies on motor ejection to deploy the devise from the rocket. The Chute Tamer just keeps the chute from deploying till your pre set time.

 

[uncle_vanya]

We need to convince them to design one with a built-in altimeter instead of a timer. Then I'd buy one in a flash.

I thought about that... it would have to be a complex design since this device is in the path of the ejection gas of the motor ejection.

 

[TWRackers]

I thought about that... it would have to be a complex design since this device is in the path of the ejection gas of the motor ejection.

Oops... forgot about that little detail.

Never mind.

 

[ultrasonicTim]

I think it's a nice idea for small lightweight rockets that might stand a chance on surviving without a parachute at all. I would stay very light and would go fairly conservative on the ejection delay.

 

[ben]

I REALLY want to know who voted "I like lawndarts" :rotflol:

 

[TWRackers]

I REALLY want to know who voted "I like lawndarts" :rotflol:

Well, it wasn't me, but "it's always fun when it happens to someone else".

 

[uncle_vanya]

I REALLY want to know who voted "I like lawndarts" :rotflol:

5 someone's at last count. I threw it in for fun. The poll is not public on purpose. Guess you'll have to just use your imagination on this one Ben.

 

[uncle_vanya]

I think it's a nice idea for small lightweight rockets that might stand a chance on surviving without a parachute at all. I would stay very light and would go fairly conservative on the ejection delay.

The device itself weighs 4.4 oz and fits into a 2" tube. I guess you could have some light and tough rockets this would work with... I don't have anything that would survive without a 'chute - but maybe with an undersized chute used as a "drogue" this could be used to deploy the main and if the main failed the fast landing wouldn't be too bad in some cases.

Another idea would be to use this to reef a 'chute and have it unfurl after a certain amount of time. That might work... hummmm.

 

[Warren]

I am new to the Rocketry Forum and am learning to use this wonderful site. Please forgive any newbie mistakes!

I am the inventor of the Chute Tamer control and appreciate the valuable concerns that have already been expressed in this thread. I am most interested in sharing my experience with the Chute Tamer contorl and learning from other experienced rocketeers.

I would like to start with a hypothetical example (#1):
Lets say that I have designed and scratch built a rocket. It is 2.5" in diameter and 40" tall with four square-shaped fins and a 29mm motor mount. I did not simulate this design, but it looks like a couple off-the-shelf kits that I have seen, so I am reasonably confident that it will fly. As with any new rocket, I plan to initially fly it with a smaller motor (maybe a G64) to determine the rockets overall flight characteristics. While I am not sure, the 2.5" cross-section and the light to medium weight of this rocket make me think that a 7 second delay is best, but I am not sure.

Surely, this is a worst-case scenario of uncertainty for using the Chute Tamer control. Would I recommend using it in this case? - YES! Here is why -

The Chute Tamer control does much more than delay the parachute deployment. Indeed in this scenario, I am uncertain about altitude, propensity to weathercock, etc., so programming a maximum parachute delay would be a very bad idea. What I do know is that a G64-7 burns for 2.5 seconds of thrust plus about 7 seconds of delay (total 9.5 seconds). Since I have not flown the rocket on this motor (or any motor), I am concerned that the delay time will be wrong and the resulting air-speed at separation will cause zipper. To avoid this, I will program the Chute Tamer control for 9.5 seconds (time of ejection) plus a little extra time for the rocket to slow down after separation (about 2 seconds), or a total delay time of 11.5 seconds from launch detection.

This will not delay the deployment of the parachute by much but will accomplish three important functions for this untested rocket: 1) provide zipper protection, 2) keep the parachute tightly bound inside the rocket during flight, preventing it from unfurling and getting stuck in the rock's air frame, and 3) provide a siren for locating my rocket after it has landed in the tall grass.

After this flight and more, I will gain experience with this rocket and various motor combinations. This experience will provide me with better altitude estimates and longer reliable delay times adding the extra convenience of delay deployment.

I have flown the Chute Tamer control in small and large rockets for dozens and dozens of flights. I have also experienced several failure modes (some quite interesting). This was all part of the learning/inventing process that I would like to share with anyone who is interested. The Chute Tamer control is now on its 4th significant design revision. The CT4 model overcomes all issues known to me.

This is why I am so excited about being a part of this discussion! I am sure there are things that I have not encountered or thought up. Please read the "Inventor's Message" at the back of the manual (https://www.locprecision.com/site/loc/ChuteTamer/User Manual - CT4 - R2color.pdf) for my motivations.

Thanks - Great Stuff!

 

[Warren]

A while back I was trying to figure out a way to create a DIY version of the Aerotech Electronic Forward Closure using a timer - when I talked about doing Dual Deployment with a pair of timers or a dual event timer I was told this was a bad idea. After thinking it through I agree.

Thoughts?

As you may expect, I have many thoughts on this and lots of experience too. First, I want to be sure that I draw a distinction between the Aerotech EFC and the Chute Tamer delayed deployment control. These two devices use similar componets to perform completely different tasks. The EFC uses a G-switch and timer to fire a black powder charge. The Chute Tamer control uses a G-switch and a timer to melt a fishing line and release a parachute. The failure modes are:

1) Timer expires too early - With EFC you get a potentially dangerous situation when the black powder ignites while the rocket is in your hand, on the pad, or on its way up at velocity:surprised:. With CT the parachute is realeased early causing it to deploy at apogee.

2) Timer expires too late, or not at all - With EFC you get a late ejection charge, or no ejection charge resulting in a lawn dart:cry:. With CT you still get the motor's ejection charge and a late parachute or no parachute (unless a suitable drouge parachute is left unbound to be deployed at apogee).

The likelyhood of either of these is small, but #1 is more suspect as it could occur as the result of prematurely activating the G-switch which is possible. The PerfectFlite timer software contains a sophisticated de-bounce algorithym to prevent shakes and drops from activating the timer. Only a sustained (2G for 0.5 seconds) acceleration will activate the timer.

The likelyhood of #2 is remote at best. In dozens of CT test flights, I have never had the G-switch fail to activate upon launch. PerfectFlite uses an expensive high quality G-switch. In addition G-switches are widely manufactured today due to their wide-spread use in the auto industry. Once the G-switch is ground tested once and verified as operational, the likelyhood that it will fail to trigger is remote.

For rockets that tumble (after separation) quickly (anything over 30-50 fps), I would strongly recommend the use of a drogue parachute to control the rocket's descent. This is no different than the standard practice when using dual deploy. (Indeed, I have seen several dual deploy flights where the second black powder charge fails to ignite causing the rocket to land under drogue only.)

 

[ultrasonicTim]

The PerfectFlite timer software contains a sophisticated de-bounce algorithym to prevent shakes and drops from activating the timer. Only a sustained (2G for 0.5 seconds) acceleration will activate the timer.

I have the microTimer and and unfortunately this de-bounce feature prevents its use with most of the Warp9 motors as the burn times are less than 0.5 seconds. :cry: I think in the EFC they have reduced the time to around 0.25 seconds so it can work with most of the W9 motors.

 

[uncle_vanya]

I have the microTimer and and unfortunately this de-bounce feature prevents its use with most of the Warp9 motors as the burn times are less than 0.5 seconds. :cry: I think in the EFC they have reduced the time to around 0.25 seconds so it can work with most of the W9 motors.

Doesn't the minitimer also have too low a G max? I think it's got a 30G switch and would need a 50G switch for some of the Warp9 applications that I have seen.

 

[uncle_vanya]

As you may expect, I have many thoughts on this and lots of experience too. First, I want to be sure that I draw a distinction between the Aerotech EFC and the Chute Tamer delayed deployment control. These two devices use similar componets to perform completely different tasks. The EFC uses a G-switch and timer to fire a black powder charge. The Chute Tamer control uses a G-switch and a timer to melt a fishing line and release a parachute. The failure modes are:

1) Timer expires too early - With EFC you get a potentially dangerous situation when the black powder ignites while the rocket is in your hand, on the pad, or on its way up at velocity:surprised:. With CT the parachute is realeased early causing it to deploy at apogee.

2) Timer expires too late, or not at all - With EFC you get a late ejection charge, or no ejection charge resulting in a lawn dart:cry:. With CT you still get the motor's ejection charge and a late parachute or no parachute (unless a suitable drouge parachute is left unbound to be deployed at apogee).

The likelyhood of either of these is small, but #1 is more suspect as it could occur as the result of prematurely activating the G-switch which is possible. The PerfectFlite timer software contains a sophisticated de-bounce algorithym to prevent shakes and drops from activating the timer. Only a sustained (2G for 0.5 seconds) acceleration will activate the timer.

The likelyhood of #2 is remote at best. In dozens of CT test flights, I have never had the G-switch fail to activate upon launch. PerfectFlite uses an expensive high quality G-switch. In addition G-switches are widely manufactured today due to their wide-spread use in the auto industry. Once the G-switch is ground tested once and verified as operational, the likelyhood that it will fail to trigger is remote.

For rockets that tumble (after separation) quickly (anything over 30-50 fps), I would strongly recommend the use of a drogue parachute to control the rocket's descent. This is no different than the standard practice when using dual deploy. (Indeed, I have seen several dual deploy flights where the second black powder charge fails to ignite causing the rocket to land under drogue only.)

All good comments. My thoughts:

Late timer without open chute = better than no ejection - but not much better. Late time is easy to see with a flight that is wind cocked or rod whipped off of vertical.

Have you tried using the 'Chute tamer as a timed "Reefing" device? In this case it would tightly hold the shroud lines only and not the whole 'chute. The chute would deploy with a partially opened 'Chute it would have less drift. Later when the timer expired the 'Chute could open fully. I'm not sure if this mode would work because obviously it changes where you "hang" the device.

 

[ultrasonicTim]

Doesn't the minitimer also have too low a G max? I think it's got a 30G switch and would need a 50G switch for some of the Warp9 applications that I have seen.

Both the EFC and mini/microTimers have a 2G switch which means it needs a minimum of 2 Gs to close (no max limit).

 

[Warren]

Have you tried using the 'Chute tamer as a timed "Reefing" device? In this case it would tightly hold the shroud lines only and not the whole 'chute. The chute would deploy with a partially opened 'Chute it would have less drift. Later when the timer expired the 'Chute could open fully. I'm not sure if this mode would work because obviously it changes where you "hang" the device.

I have not tried this, but see no reason that it would not work. The only limitation would be pace in the body tube to accomodate. I would load the laundry as follows: fold main chute (without folding the shroud lines) and place the main plus shock cord into the nomex blanket. Then I would bind the shroud lines (at the desired distance from the chute) to the Chute Tamer control. The shock cord, main chute, and Chute Tamer control are all connected separately to the eyebolt of the nose cone or payload bay. Also connect a drogue if desired. All this would be loaded into the body tube in this same order to be ejected at apogee.

I will give this a try at some point. I am envisioning some extra fabric wrapped around the shroud lines that is attached somewhere, but falls free. The shroud line/fabric bundle would be easy to bind to the Chute Tamer control. This configuration would be similar to using a properly sized drogue chute.

Thank you for the added ideas about Chute Tamer functionality!

 

[Warren]

Late timer without open chute = better than no ejection - but not much better. Late time is easy to see with a flight that is wind cocked or rod whipped off of vertical.

In my experience an open/tumbling rocket (unstable but no chute) reaches its maximum velocity quickly. This maximum tumbling velocity depends on the cross-sectional surface area of the rocket, the rocket's weight, and a bunch of other stuff like air density. I have attached an excel file that shows tumble velocity for various combinations of these factors. In any case, it takes a very "dense" rocket (heavy with little surface area) to tumble faster than 60 fps (3 times 20 fps under chute).

On the other hand, a rocket that comes down bullistic (as it went up) presents a very small profile to the air stream and may not reach its maximum speed before hitting the ground. A bullistic rocket can easily be tarvelling in excess of 300-500 fps.

In my book, an open rocket (especially using a drogue) is much safer than a bullistic recovery.

View attachment ChuteTamer.zip

 

[Warren]

I have the microTimer and and unfortunately this de-bounce feature prevents its use with most of the Warp9 motors as the burn times are less than 0.5 seconds. :cry: I think in the EFC they have reduced the time to around 0.25 seconds so it can work with most of the W9 motors.

Thank you for this information. I will add this to the Chute Tamer manual and FAQ on the web (when they are published). Without a similar modification to the PerfectFlite mini timer in the Chute Tamer control, CT is not suitable for use with Warp9 propellant engines.

I am curious: When does the Aerotech EFC get turned on? I am having trouble imaging loading the engine on the launch pad, so I am assuming that the EFC is armed at the prep table, and stays armed at the LSO table, in line waiting to launch, etc...:surprised: Is this correct?

The Chute Tamer control can easily be turned on at the pad. Because the parachute is bound, it slides easily in and out of the body tube. Just before loading onto the rod/rail slide it out and turn it on (listening for the correct delay time and verifying heating element continuity). If this is not convenient, then CT can be turned on at the prep table. There will be a tone indicating heating element continuity which will stop if the timer is activated. In addition, a locating siren sounds after the timer completes its operation. In either case, it will be obvious if the parachute is released prior to launch.

 

[astrowolf67]

I started flying dual deploy with a blacksky timer, simply because I could pay less for it (as a high school student). It took some very careful calculation of altitude, descent rate under drogue, weathercocking, and some fudge factor. I found that after some trial and error, I could get my rocket to dual deploy in the 400-600 region, but if there is any abnormality in the flight path, you're looking at a charge going off on the ground instead of at 500ft...:cry:

In my opinion/experience, pay a little more (now its not even that much) and go with the altimeter.

Bruce

I haven't been on in a while, but, in my research of the Chute Tamer, came across this thread. From what I've read in the online manual, there is no live charge, which makes the CT very safe to use. It looks like it can even be tested while still held in the hand, with little to no danger of even getting burned.

 

[uncle_vanya]

I haven't been on in a while, but, in my research of the Chute Tamer, came across this thread. From what I've read in the online manual, there is no live charge, which makes the CT very safe to use. It looks like it can even be tested while still held in the hand, with little to no danger of even getting burned.

That's fair. The only real danger is with a flight that is not vertical the rocket could fail to deploy the main before the rocket hits the ground at 50-60' per second. Faster than ideal but not ballistic and no danger of black powder ejection charge causing fire or other damage. That does put this in better perspective I think.

 

[flight4]

I like this discussion. Great information. Hell, it might be worth a try

 

[Warren]

I like this discussion. Great information. Hell, it might be worth a try

A discussion of "weathercocking" might also be in order. The tendancy of some rockets to fly in a direction other than straight up can be unerving if it is not well understood.

Stable rockets always fly into the greatest "wind". Because a stable rocket's center of pressure (CP) is behind its center of gravity (CG), the forces of the "wind" cause the rocket to rotate around the CG (tail down). Another debate could be how "stable" a rocket design should be: how many body tube diameters (calipers) in length should there be between the (lower) CP and the (higher) CG. Generally, a minimum of one and more like two or more calipers are recommended.

On a day with no breeze-wind, the only wind that the rocket experiences is the downward-wind created by the rocket thrusting upwards. Under these conditions, the faster the rocket is moving the stronger the downward-wind and the more stable the rocket becomes to any horzontal breeze-wind disturbance.

On a day when the breeze-wind is strong, the rocket experiences two types of wind during its flight: breeze-wind and downward-wind. It is the (vector) sum of these two winds that determine the reaction of the rocket. Because the rocket accelerates during the engine's boost phase, the rocket's upward velocity is slowest at the begining of its launch. The slower the rocket's upward velocity, the less downward-wind and the more RELATIVE breeze-wind. Thus at the beginning of launch, the breeze-wind component is at its strongest relative to the downward-wind.

To aide in stabilizing the rocket, we use a launch rod or rail. The recommended 5:1 thrust to rocket weight ratio is a rule of thumb intended to give the rocket enough upward velocity (downward-wind) to be stable enough, even with a breeze-wind.

I have found a couple of techniques that at the launch pad that reduce weathercocking for any given rocket. First, I always place the rocket on the down-breeze side of the rod or rail. this way as the rocket accelerates upward, it does not have a tendancey to rotate around the rod or bind in the rail, slowing its upward acceleration. Second, if the rocket is known to weathercock lots, I will point the rod slightly DOWN-breeze. When the rocket leaves the rod and rotates into the breeze-wind, it then takes a more upwards trajectory.

The reason some rockets are more prone to weather-cock than others is in their design. The longer the distance between CG and CP, the more susceptible to breeze-wind the rocket will be. I find that many of today's kits are more than two calipers and thus somewhat over-stable. Be careful flying overly tall rockets (raises the CG), or rockets with large fin structures (lowers the CP) on their first flight.

Regarding the Chute Tamer control, the important thing is to know the flight history of the rocket. Proper location of the Chute Tamer control will leave the rocket's CG to CP relationship unchanged. Chute Tamer or not, any rocket with a severe tendancy to weathercock, should be saved for a day with little to no breeze-wind. If flown with the Chute Tamer control, it should be flown with a very short Chute Tamer delay equal to the engine's thrust time plus delay time plus a couple of seconds as well as with a drogue parachute.

Please let me know if this information is helpful or just redundant with other parts of this forum. Thanks -

 

[mr_fixit]

Warren,

That was very useful information, as many times as I've heard the stability discussion, it never hurts to hear it again a little bit differently. Thanks. With regards to the CT, seems like a very viable alternative for the conversion of single deploy rockets to dual deploy. I also really like the choice of not having to use BP for the second ejection charge. My daughter and I almost got hit with a large NC from someone setting up a DD rocket not facing downrange, but sideways because it fit on their table better. Kaboom, sorry

Couple of thoughts along the way:

a. seems kind of expensive off the top. (compared to alt/bp but probably not)
b. approx $1.60 per flight
c. like the locator beeper feature
d. like the simplicity of the device, seems like it would be great for young ones as well.

Couple of questions:

a. how durable is it, can it survive a tumble recovery (which is much safer than a ballistic something or other!)
b. can it survive a lawndart?
c. any problems with the tether point to date?
d. is the 40°F a hard and fast limitation? We fly in the northeast and have flown in single digit weather.
e. any possibility of having an input from an altimiter to trigger the device?
f. the possiblity of having a device that only receives an input from a timer or alt. only?
g. about how many are in use/sold now?

Anyhow, great thread and information. Looks like a really great product and I know Barry would not carry something that he wouldn't back 100%, right Barry?

Thanks again,

Tom

 

[Warren]

Couple of questions:

a. how durable is it, can it survive a tumble recovery (which is much safer than a ballistic something or other!)
b. can it survive a lawndart?
c. any problems with the tether point to date?
d. is the 40°F a hard and fast limitation? We fly in the northeast and have flown in single digit weather.
e. any possibility of having an input from an altimiter to trigger the device?
f. the possiblity of having a device that only receives an input from a timer or alt. only?
g. about how many are in use/sold now?

These are great questions. Thanks for asking. Here are some answers:

a) b) How Durable? I have had the misfortune of two flights with very hard landings during various CT tests. In the first example, the rocket engine's ejection charge never lit. (Examination of the recovered rocket pieces showed no burning of the ejection charge. Discussion within SkyBusters club was that the age of the reload required sanding or scoring of the delay element to ensure proper ignition of the delay.)

The rocket came in ballistic in a large patch of tall grass. Ugh - Take the shovel and hope to get lucky! Turns out, the engine casing and the Chute Tamer control were the only two components undamaged. In fact, the Chute Tamer control had completed its sequence of operations normally and its siren was blaring. The siren made the half-submerdged rocket parts extremely easy to find out in the tall grass!

The second hard landing occured when the rocket engine ejection charge broke the attachment point between the shock cord and the nose cone. (I had improperly attached the shock cord to some kevlar cord and tied this to the "flashing" on either side of the nose cone's eyebolt hole. After a dozen flights, the nose cone flashing failed.)

So the rocket with shock cord and attached Chute Tamer control came down separately from the nose cone. The abscence of the nose cone allowed the rocket to become stable in its descent. (I should have included a small drogue parachute, but did not. ) The rocket body tube (no nose cone) lawn darted into the open field, burying itself about six inches in the ground.

The Chute Tamer control with the bound parachute was outside the protection of the body tube and landed hard on the field next to the rocket. The Chute Tamer control had several grass stains and a bit of mud, all of which cleaned up nicely. Today, I can not tell you which of my CT controls this was because there was no damage externally or internally to the CT unit.

c) Tether Point Problems? I have not had any problems. The nylon strap is attached to the ABS enclosure with two barrel bolts. The plastic D-ring has not failed during tests.

d) 40 Degrees? This is straight from the PerfectFlite manual. The rest of the CT unit (except the cutter) could care less about weather or temperature. The issue with the cutter is that it melts the fishing line with heat . The nichrome cutter wire is energized by the timer circuit for a fixed period of time. The amount of current that flows through the wire depends on this time interval and the freshness of the battery (among other less important things). The Nichrome wire heats from its current temperature to above the melting temperature of nylon (around 450 degrees F). The lower the current temp of the wire, the more heating that has to be done.

I have tested the CT control in Ohio winters and found that prior cutter designs did not get hot enough in the very cold weather. The current cutter design has not failed me in the cold weather, but I would like to gather more testing on this issue. (Remeber that the temperature is colder, the higher the altitude.)

e) f) Use an Altimeter? Yes! The heating cutter can be energized by any "ematch" style output. A barometric altimeter has one or more of these outputs. The timer has the added advantage of not being pressure sensitive and can thus be placed inside the body tube where the engine's ejection charge goes off. This would damage a barometric sensor (thus the separate compartment for dual deployment). The patent that has been filed for the CT control includes the use of many triggering mechanisms including timers, barometric sensors, remote control signals, etc...

g) How Many Sold? Apart from test units, there are four "production" Chute Tamer controls that have been purchased. This product is brand new. I started selling them on July 27 of this year (2007). I had the chance to demonstrate the production version to Barry Lynch (of LOC/Precision) at the NYPower launch. He immediately bought one and had it evaluated/tested. Based on his evaluation and my enthusiasm for his products and well deserved reputation, he and I agreed to an exclusive sales arrangement. If you want to purchase one, check out the LOC/Precision web site (www.LOCPrecision.com) or go to www.ChuteTamer.com.

Whew - great questions -

 

[wkissee]

I flew with a Chute Tamer for the first time this weekend and it works GREAT!

I launched Pinky, my PML Callisto, four times this weekend with the Chute Tamer it worked just as Warren said it would. The hardest part of using it is tying the @%#*#&$ monofilament (once my son got out to the launch and I had a “third hand” it was much easier)! LOL! The next tricky thing is calculating the timing on the timer, I used RockSim for my time calculations (I hate complex math problems) by setting the sims for no deployment. This seemed to work fairly well, the The following is an outline of the flights and my observations:

Flight #1:
- First time using it.
- Motor: AT 29mm H165R w/ Med. Delay time
- Time setting: 15 secs
- Result: The monofilament line did not burn through but the chute released at apogee. Successful recovery.
- Conclusion: Problem was user caused and not device/design caused. I did not have the line tied tight enough and the ejection charge blew the chute out from under the line (thankfully) allowing the chute to deploy as normal.

Flight #2:
- Motor: AT 29mm H165R w/ Med. Delay time
- Time setting: 15 secs
- Result: The Chute Tamer worked perfectly, but deployment was too soon, later than an apogee deployment, but still too soon.
- Conclusion: Set the timer for a longer delay. I began suspecting that using RockSim with no deployment settings may have it’s flaws.

Flight #3:
- Motor: AT 38mm I300T w/ Med. Delay time
- Time setting: 25 secs
- Result: AWESOME launch, watched the deployment at apogee, but lost sight of it during the free-fall. As this was my last launch of the day, I was feeling pretty bummed while I was packing up my stuff and then felt REALLY bummed while I was driving home because I realized that I had not only lost my beloved Pinky, but also my Chute Tamer and motor casing as well. :cry:

That evening while I was fixing dinner and describing the day’s events to my wife, I got a call from the RSO out at the launch and he told me that someone had found Pinky and it was in tact! WOO HOO! Pinky lives!

When I got to the launch the next morning, I bee-lined straight to the RSO table and recovered Pinky; she was intact and all was well. Now back to the Chute Tamer:

Flight #3 Continued:
- Conclusion: I never found out who found Pinky (thank you whoever you are) so I am unable to know for sure how she was found, but I do know the following:
o I did not see a chute deployment at apogee (I observed the free-fall)
o The chute was not still attached to the Chute Tamer when I got the rocket back from the RSO
o Pinky was intact with no damage
So I am going to assume that the Chute Tamer worked as designed

Flight #4:

- Motor: AT 29mm H210R w/ Med. Delay time
- Time setting: 19.9 secs
- Result: The Chute Tamer worked perfectly, but deployment was too soon, later than an apogee deployment, but still too soon.
- Conclusion: I saw the whole flight and the Chute Tamer worked PERFECTLY. I still need to set the timer for a longer delay. I realized that the problem with figuring the time for the timer with RocSim in the manner that I was is that the sim does not account for the fact that the rocket breaks apart when the motor ejection occurs and therefore slows the decent of the rocket, maybe I will have to use Warren’s calculation sheets 

All in all this is a GREAT product and once I get the timing thing down it will work even better! Thanks Warren for the work that you put into this!