Low Power pads (Distance)

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The clubs in South Carolina have been discussing low power pad distance and motor launched off of them. The reason we have discussed the topic is the every increasing thrust for F motors. Some clubs launch them from low power and others do not. I have noticed there is a difference between TRA and NAR in their pad locations.

For TRA: the safe distance to Spectators for a Model Rocket launch is listed as 50 feet or 15 meters. I would assume that is the distance from the RSO or LCO table, also.

For NAR: the safe distance of at least 15 feet away when launching rockets with D motors or smaller, and 30 feet when launching larger rockets.

How far do you set up and what is you cut off to bounce it out to mid power (100 + feet)?
 
I'd go with the TRA minimum distance since most launches are mixed power levels. A few extra feet of separation is cheap insurance in case something goes wrong.

That is what I am recommending, with F motors slipping out to 100 feet. Some of those boogers are scary. I, especially, like being a little further away from an F79, F240, F120, and quite a few others. Composite F motors can put a hop in your step.
 
For TRA: the safe distance to Spectators for a Model Rocket launch is listed as 50 feet or 15 meters. I would assume that is the distance from the RSO or LCO table, also.

The bolded assumption is not correct:

https://www.tripoli.org/content.aspx?page_id=22&club_id=795696&module_id=520420 said:
12-3The minimum distance to Range Personnel when Model Rockets are launched shall be 30 feet.

I, especially, like being a little further away from an F79, F240, F120, and quite a few others.

The bolded motors are not considered "Model Rocket Motors" by Tripoli and are required to be launched in the High Power area, at a minimum of 100ft, with the H-J motors. The NAR Safety Code is less clear.

Personally, I think G's from 30-50 feet are a real treat!
 
The bolded assumption is not correct:

[quote link="[URL]https://www.tripoli.org/content.aspx?page_id=22&club_id=795696&module_id=520420[/URL]"]tes
The bolded motors are not considered "Model Rocket Motors" by Tripoli and are required to be launched in the High Power area, at a minimum of 100ft, with the H-J motors. The NAR Safety Code is less clear.

Personally, I think G's from 30-50 feet are a real treat!

Thanks. That might be the difference. We have never allowed anything that powerful from low power. I have seen it done.

I think the problem with most setups I have seen is that the spectators and RSO/LCO are often at the same location right behind the flight line.

12-3The minimum distance to Range Personnel when Model Rockets are launched shall be 30 feet.
12-4The minimum distance to any Spectator when Model Rockets are launched shall be 50 feet.
 
The clubs in South Carolina have been discussing low power pad distance and motor launched off of them. The reason we have discussed the topic is the every increasing thrust for F motors. Some clubs launch them from low power and others do not. I have noticed there is a difference between TRA and NAR in their pad locations.

Before we get too deep, I would re-classify F-motors as distinctly non low power. More like Mid-power.
For all practical purposes, these motors would go with larger and heavier airframes, so tiny 1/8" or 3/16" rods are out.
Longer 1/4" rods or mini-rails are in, and those are incompatible with the usual low-power rocket lugs.
So you will likely have a dedicated mid-power pad or two, and it should be positioned further away from the spectators/RSO table than basic LP pads.

For TRA: the safe distance to Spectators for a Model Rocket launch is listed as 50 feet or 15 meters. I would assume that is the distance from the RSO or LCO table, also.

That's probably distance to spectators.
At some sites, logistics dictate that the RSO table and spectators are in close proximity with each other. At others, spectators stay further away, near their cars or tents. Not sure what your site looks like.

How far do you set up and what is you cut off to bounce it out to mid power (100 + feet)?

Usually, MP pad(s) are further away from RSO/spectators and LP, but not as far as HP pads. For HP as well, there are "basic" HP pads (100 feet away), and a larger K/L/cluster HP pad that sites further (300+ft away).
I never physically managed the exact distance, just know where the pads are usually setup.

HTH,
a
 
Before we get too deep, I would re-classify F-motors as distinctly non low power. More like Mid-power.
For all practical purposes, these motors would go with larger and heavier airframes, so tiny 1/8" or 3/16" rods are out.
Longer 1/4" rods or mini-rails are in, and those are incompatible with the usual low-power rocket lugs.
So you will likely have a dedicated mid-power pad or two, and it should be positioned further away from the spectators/RSO table than basic LP pads.



That's probably distance to spectators.
At some sites, logistics dictate that the RSO table and spectators are in close proximity with each other. At others, spectators stay further away, near their cars or tents. Not sure what your site looks like.



Usually, MP pad(s) are further away from RSO/spectators and LP, but not as far as HP pads. For HP as well, there are "basic" HP pads (100 feet away), and a larger K/L/cluster HP pad that sites further (300+ft away).
I never physically managed the exact distance, just know where the pads are usually setup.

HTH,
a

We usually set up our RSO and LCO table against the flight line so the LCO and RSO can manage folks standing behind the flight line.

Currently, we follow the rules by NAR for NAR launches and TRA for TRA launches and we are considering going with the low power standard for both. I think we will go with 50 feet from the flight line and just make it easy. MP at 100 and 300 for HP. Away cell at 500 or greater.
 
Using motor size alone isn't an accurate measure to determine clearances. It is best to use combined total impulse that way clusters can also be analyzed.

I follow this chart, from this link.

Launch site Dimensions and Distance to Launch Pad.png
 
We put the model rocket area at least 50 feet away, often further than that, as much as 100 feet. We typically put high power pads 200 feet away. While I get the impulse to put F and G motors further away, doing so creates a new problem, especially if they are put with high power pads. Youth under 18 can launch model rockets, including those with F and G motors, but they can’t go to a high power area.
 
We fly mostly mid- and high- power. We also use a wireless launch system. We nominally set up at a minimum distance of 100 feet. However, if launching low-powered rockets, we allow photographers (and others) to move closer if they want.
 
For NAR: the safe distance of at least 15 feet away when launching rockets with D motors or smaller, and 30 feet when launching larger rockets.

How far do you set up and what is you cut off to bounce it out to mid power (100 + feet)?

We set up 15-feet away for model rockets up to 20 N-s, and at least 30-feet away for model rockets in excess of 20 N-s.

We never "bounce" mid power model rockets out to 100-feet. We consider any motor in excess of 80 N average thrust to be a high power motor, and not a "mid power" motor that needs bouncing. We don't allow high power flights at our current field.
 
We use 50 ft extension cords from our LPR controller to the 8 pads, with 6 ft. clip whips on the end of those. That keeps everyone, range personnel and spectators 50 ft from low power pads. Since there really isn't a MPR definition in the safety codes, we go with the codes and G and below, and <81 N avg. motors go from the LPR pads. We have 3 1/8 rods and also 3 1010 rails along with a couple 3/16 rods and a single 1/4 rod.

We also extend the distance on the HPR. The first row is about 150 ft out, second row 250 ft. and all L and larger motors go to the away about 550 ft. out.
 
The clubs in South Carolina have been discussing low power pad distance and motor launched off of them. The reason we have discussed the topic is the every increasing thrust for F motors. Some clubs launch them from low power and others do not. I have noticed there is a difference between TRA and NAR in their pad locations.

For TRA: the safe distance to Spectators for a Model Rocket launch is listed as 50 feet or 15 meters. I would assume that is the distance from the RSO or LCO table, also.

For NAR: the safe distance of at least 15 feet away when launching rockets with D motors or smaller, and 30 feet when launching larger rockets.

How far do you set up and what is you cut off to bounce it out to mid power (100 + feet)?
I dont understand all the different answers. The distance requirments are written in the safety guides in the NAR and Tripoli web site. These are minimum distances. If you fly NAR, go by the NAR safety codes, if Tripoli go by the TRA safety requirements i prefer to follow the TRA club rules except if NAR safery codes are more conservative and whichever clubs rules are more conservative would go with that personally
 
ROC puts the LPR (up to and including “G”) pads 150 feet from seated spectators. We have a 50 ft wide “standing/walking only” zone followed by another 100 feet of roped-off range before you get to our LPR pads. Technically, they are 100 ft from the LCO/Pad Manager rangehead.
 
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ROC puts the LPR (up to and including “G”) pads 150 feet from seated spectators. We have a 50 ft wide “standing/walking only” zone followed by another 100 feet of roped-off range before you get to our LPR pads. Technically, they are 100 ft from the LCO/Pad Manager rangehead.
Why so far away?
 
Why so far away?
We have LOTS of spectators, many of which don’t really understand the inherent risk of a “G-powered” land shark.

Also, after being sued several years ago, we’re really conservative with distances.

Oh, and we have the room, 2560 acres of dry lakebed…
 
Ah, being sued will do that to anyone.
Yup.
We have LOTS of spectators, many of which don’t really understand the inherent risk of a “G-powered” land shark.

Also, after being sued several years ago, we’re really conservative with distances.

Oh, and we have the room, 2560 acres of dry lakebed…
It is good to be a little conservative with measurements.
 
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