Flight line orientation

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LW Bercini

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The debate about drag races has inspired me to ask about the proper way to lay out a high power launch

From the outset, let me say this, I am NOT a high power guy. I am just a mid-power guy who attends launches that include a significant number of high power flights.

Based on what I have seen, pads seem to be laid out with proper distances. But is there a rule of thumb about distance and/or orientation of the flight line with regard to the LCO?

Here is my observation, based on attending various 2-day launches around the Southeast: regardless of the flight line orientation, regardless of the wind conditions, regardless how far away the pads are, there will be at least one instance of a failed recovery dropping on or near the flight line.

I know this statement is probably anecdotal. It is simply my observation. Do you folks observe the same thing? If not, is there something wrong with the way ranges are being set up around here?
 
My car once got hit by a falling rocket, it was at least 80 yards from the pad. I don't think there was anything wrong with the range set up, it's just hard to predict which direction the rockets will go, they don't necessarily fall in the direction of the wind. But all other things being equal, it's preferable to have the flight line upwind.
 
I'd say we get about six cars hit a year. But here's the problem.

At our summer sod farm, the owner tells us where we can launch. He is looking to minimize damage to his grass, and wants to keep his watering machines turned on in certain fields.

At our winter crop farm, we leave the pads up 24X7 so that we can start at 9:00 AM. The equipment trailer gets parked and does not move. So we don't have the option of picking a new flight orientation on the fly.

We try to be smart about not allowing heavier rockets to launch if the wind is toward the flight line.
 
The range should be set up so that at no time are any rockets over the flight line, or spectators heads.

Doesnt always happen and consitions can change without warning. And some rockets just take their own path
 
conditions can change without warning. And some rockets just take their own path

And based on what I see, this seems to be the state of affairs. As the adage goes "the best laid plans of mice and men..."

There doesn't seem to be any way to avoid high power rockets (or parts thereof) from falling around the flight line.
 
On days when the wind is coming at the flight line, LCO shouls make frequent announcements that this is the case, and anyone concerned about safety should leave the range. If you stay, you are accepting the risk.
 
Situational awareness, I cant say this enough, While at a red sox game, We arrived early to watch batting practice and to catch a few in the outfield (there are alot of players who can hit home runs during practice, Well, I grabbed one, and like 3 homers later, the ball comes flying in 5 rows behind me and flat out slams a guy sitting in his seat who was oblivious to where he was. He got his world rocked in the span of 1 second. He was not paying attention and deserved to be hit due to his own stupidity. The same goes for rockets, If your situational awareness is lax, expect the worse.

You cant go to a baseball game and not expect the ball to leave the field, and the same with rockets, If it goes up.. it will come down.
 
On days when the wind is coming at the flight line, LCO shouls make frequent announcements that this is the case, and anyone concerned about safety should leave the range. If you stay, you are accepting the risk.

This is the most incorrect statement I have ever read on this forum. If wind is pushing rockets over the flight line- operations should be shut down. period.
 
You cant go to a baseball game and not expect the ball to leave the field, and the same with rockets, If it goes up.. it will come down.

however, rocket ranges should be set up with a ballistic recovery zone that is not populated. To take the baseball analogy, there should be no seats in the outfield.
 
Situational awareness, I cant say this enough, While at a red sox game, We arrived early to watch batting practice and to catch a few in the outfield (there are alot of players who can hit home runs during practice, Well, I grabbed one, and like 3 homers later, the ball comes flying in 5 rows behind me and flat out slams a guy sitting in his seat who was oblivious to where he was. He got his world rocked in the span of 1 second. He was not paying attention and deserved to be hit due to his own stupidity. The same goes for rockets, If your situational awareness is lax, expect the worse.

You cant go to a baseball game and not expect the ball to leave the field, and the same with rockets, If it goes up.. it will come down.

Not really arguing anything here agains PD location except for the above statement.

Yep there are inherent dangers in nearly any spectator sport but he deserved to be hit because he was oblivious and made a stupid decision? Wow that's kinda harsh, so my kids playing at a launch deserve it?

A love to see drag races as much as anyone - but 20 L powered rockets going completely out of site are another matter, you literally cannot track that many rockets and make sure that separation charges occurred, nothing is coming in hot etc. I yelled for my family to get in the truck as they announced a big drag race - even then one could come in ballistic too fast to see or move - prolly go right through the top of a car - just thin metal. It is freaking dangerous - however So is any launch. Attending beware - LCO's are typically very good about announcing this at launches I've attended.

I think pads setup correctly - but Launch director should pass on to Pad managers to watch rail orientation as soon as a rocket goes toward flight line.
 
Generally our club sets up the range as close to a crosswind situation as possible. By doing so rockets that weathercock don't come directly over the spectators, we also do not allow the launch rods to be angled any direction that will put the rocket over the spectators. Typical winds on our field are from the SW and the flight line goes East to West. The spectator/prep area is directly South of the flight line and the recovery area is North (due to the winds most recoveries are in the NE area of the field). Any rockets that weathercock tend to land SW of the flight line and ballistic events rarely occur in either the spectator or prep areas.
 
Not really arguing anything here agains PD location except for the above statement.

Yep there are inherent dangers in nearly any spectator sport but he deserved to be hit because he was oblivious and made a stupid decision? Wow that's kinda harsh, so my kids playing at a launch deserve it?

Sitting in the left field outfield 5 rows back while balls are comming in continuously, and not having a clue as to what's going on.. yes.. he deserved to be hit.. if he stood in traffic on route 95 wearing black on a moonless night and get hit.. also deserved... common sense isn't so common..

Play stupid games win stupid prizes...
 
A copy of the movie ""Trolls"

I already own all of your movies, Dave.

Meanwhile, if you want to come down and tell the MDRA BoD that they need to start shutting down flight operations due to wind direction, I'm sure they will give you a hearing. I am not on the BoD, so I cannot comment further.
 
NFPA 1127 4.17.1 no person shall ignite and launch a high power rocket horizontally, at a target, or so the rockets path during ascent phase is intended to go into clouds, over the heads of spectators, or beyond the boundaries of the launch site.....



does MDRA not follow the NFPA codes?
 
On days when the wind is coming at the flight line, LCO shouls make frequent announcements that this is the case, and anyone concerned about safety should leave the range. If you stay, you are accepting the risk.

With today's litigious society, you honestly believe a statement like that!
Unfortunately this hobby doesn't have the luxury of moving on unscathed AFTER a serious incident and we must always try and take all steps to prevent the "big one" from happening.
It is the only prudent track! The truth of the matter is, days of sticking our heads in the sand are over.

Greg
 
Sitting in the left field outfield 5 rows back while balls are comming in continuously, and not having a clue as to what's going on.. yes.. he deserved to be hit.. if he stood in traffic on route 95 wearing black on a moonless night and get hit.. also deserved... common sense isn't so common..

Play stupid games win stupid prizes...


Nope your wrong!

If they life they sue and get a monetary prize
If they don't live, the family sues and gets a monetary prize

Greg
 
NFPA 1127 4.17.1 no person shall ignite and launch a high power rocket horizontally, at a target, or so the rockets path during ascent phase is intended to go into clouds, over the heads of spectators, or beyond the boundaries of the launch site.....



does MDRA not follow the NFPA codes?

No one launching intends for his/her rocket to go over the heads of spectators during the ascent phase. Angle your pad with the wind so that it weathercocks back away from the flight line. Nothing in the safety code says that rockets can't drift over the flight line during descent; and even if it happens during ascent, as long as it was not intended to do so covers the code. Am I missing something?
 
No one launching intends for his/her rocket to go over the heads of spectators during the ascent phase. Angle your pad with the wind so that it weathercocks back away from the flight line. Nothing in the safety code says that rockets can't drift over the flight line during descent; and even if it happens during ascent, as long as it was not intended to do so covers the code. Am I missing something?

Yes, that rockets can not be launched over the flight line.
 
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With today's litigious society, you honestly believe a statement like that!
Unfortunately this hobby doesn't have the luxury of moving on unscathed AFTER a serious incident and we must always try and take all steps to prevent the "big one" from happening.
It is the only prudent track! The truth of the matter is, days of sticking our heads in the sand are over.

Greg

Who said anything about heads in the sand? I am simply saying that you do not need to shut down operations if you take the correct precautions when the wind is not favorable. Suppose you have six launches in a row where the wind is toward the flight line, and you cancel them all. Pretty soon you don't have a club.
 
Who said anything about heads in the sand? I am simply saying that you do not need to shut down operations if you take the correct precautions when the wind is not favorable. Suppose you have six launches in a row where the wind is toward the flight line, and you cancel them all. Pretty soon you don't have a club.


You're just embarrassing yourself now.
 
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Okay, I'm done. Once an argument has been reduced to ad hominem attacks, there is no more room for discussion. Too bad you weren't willing to engage with me on an intelligent level. Maybe you would have changed my mind. Instead, I'll just go away insulted, and you win.
 
Okay, I'm done. Once an argument has been reduced to ad hominem attacks, there is no more room for discussion. Too bad you weren't willing to engage with me on an intelligent level. Maybe you would have changed my mind. Instead, I'll just go away insulted, and you win.

In the interest of clarity... Your statement that when the wind makes flying unsafe, they should just make an announcement and then it's all cool, is what I consider an issue.

If the wind is pushing all flights over the flight line despite rod angles and placement.... you need to stop flying. If you continue to launch you can say " i didn't intend for that" all day long, but if you know it's going there....thats intent. I am not talking about the occasional stray flight. those happen everywhere.

When there's a burn ban, you don't just say " well that would kill the whole season!" and launch anyways.
When the wind is pushing rockets under ascent over the flight line.... if you can't correct the situation by moving the flight line, or changing flight angles... you can not launch. It doesn't matter how many launches get canceled for it. You have to maintain a safe ballistic recovery area. If you can't.... shut it down.
 
My question is if we should differentiate between the powered flight/coast phase of the launch and the descent portion and then lay out the field to accommodate one more than the other. The former (to me) absolutely, the latter gets sticky. I have been on fields where the wind shifts constantly. Should we launch something like a Nike Smoke every hour to check the winds at varying altitudes? Or do we declare you don't launch except in dead calm?
 
I don't think descent is an issue, as I understand it the goal is to avoid ballistic returns in populated areas. Something under chute or broken in half isn't ideal landing in a lot, but it's manageable.
 
In the interest of clarity... Your statement that when the wind makes flying unsafe, they should just make an announcement and then it's all cool, is what I consider an issue.

If the wind is pushing all flights over the flight line despite rod angles and placement.... you need to stop flying. If you continue to launch you can say " i didn't intend for that" all day long, but if you know it's going there....thats intent. I am not talking about the occasional stray flight. those happen everywhere.

When there's a burn ban, you don't just say " well that would kill the whole season!" and launch anyways.
When the wind is pushing rockets under ascent over the flight line.... if you can't correct the situation by moving the flight line, or changing flight angles... you can not launch. It doesn't matter how many launches get canceled for it. You have to maintain a safe ballistic recovery area. If you can't.... shut it down.

I will agree with that. All flights going over the line, during ascent, cannot be corrected. Move the flight line, or shut down. My statement started, "On days when the wind is coming at the flight line...". Too broad of a statement. Likewise, it is too broad of a statement to say that if the wind is toward the flight line, shut down operations. Now that we have clarified the behavior of the rockets and frequency of the problem, I agree fully.
 
And yet, it was what my question was about.

So. Much. Argument. Over. A. Different. Topic.

it all ties in really. If done right, MOsT flights should not be dropping in on the line. One or two may blow over and you can't always do anything about that if they're separated or under chute.
 
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