Derek Deville's Black Dragon

Check out this website of the Black Dragon and the video of its launch at the Florida Winter Nationals.

https://www.ddeville.com/derek/BlackDragon.htm

Dan

Interesting to note a couple of things in the photos on that link;

Bummer that there appears to be some zipper damage to the top of the booster (always a bummer to see that, especially on big money projects)

And (knowing this is touchy question to ask at times) - looking at the first picture of the actual launch on that P motor, how far away are those people in the background? I trust with the flat topography and lack of other features such as trees and bushes to provide better depth perception that those folks are a long way away and the picture is deceiving.......

They are farther away then it looks. Derek used some launch equipment that belongs to one of our club members so we walked out to the pad after the launch to get it and that tractor is far away. How far I don't know. One of the guys in the photo was one of the people running the launch so I'm sure he made sure they were far enough away.

Dan

Fore Check said:

Bummer that there appears to be some zipper damage to the top of the booster (always a bummer to see that, especially on big money projects)

Click to expand...

Big projects like Derek's and even our 125lbs Mega K-1 we flew on an N2800 typically don't last long to begin with. The size and weight make them vunerable to zippers if just something minor goes wrong on deployment despite any airframe strengthening one does to attempt to prevent it. Often, these giant projects are a "one-shot" deal...get it up on a cool, big motor and recover it successfully is considered a major success. Big deal....a relatively small zipper on a 375lbs/21 ft rocket. Few rockets the size of the Black Dragon come back completely undamaged.

While I know that looks can be deceiving, I'd like to know exactly how far they were from the rocket when it took off. Looking through all of the photos, it doesn't look like they were all that far away.

SpartaChris said:

While I know that looks can be deceiving, I'd like to know exactly how far they were from the rocket when it took off. Looking through all of the photos, it doesn't look like they were all that far away.

Click to expand...

I agree. To me that only looks like 500-800 feet. And they are all ducking behind the tractor

Ben

Depth of field,

look at the photo of them setting up the pad when the telephoto lens is not used. See how far the tractor is away.

Look at other photos and see how far the pad is from the flight line.

Now with the photographer way way back, and telephoto at super zoom, the depth distances between the pad and tractor seem like 10-25 feet.

Art Upton said:

Depth of field,

look at the photo of them setting up the pad when the telephoto lens is not used. See how far the tractor is away.

Look at other photos and see how far the pad is from the flight line.

Now with the photographer way way back, and telephoto at super zoom, the depth distances between the pad and tractor seem like 10-25 feet.

Click to expand...

I'm not referring to the tractor.

If you look at this photo:

https://www.ddeville.com/images/Rocket/rocket 187.JPG

and this photo:

https://www.ddeville.com/images/Rocket/rocket 142.JPG

that ridgeline in the background doesn't look all that far away. Maybe a couple hundred feet at most? These are photos taken without the telephoto lens, correct?

And then in this photo:

https://www.ddeville.com/images/Rocket/rocket 186.JPG

The group of people on the left appear to be just on the other side of that same ridgeline?

I guess my point in all of this is that if Andy's project can be scrutinized to death to see if all of the safety code requirements were met, then why shouldn't EVERY project, including this one?

"I guess my point in all of this is that if Andy's project can be scrutinized to death to see if all of the safety code requirements were met, then why shouldn't EVERY project, including this one?" - Spartachris

Well said Chris.

For the record, I totally dig the project. As for the people being far enough away, while I understand the safety code, I'm also a big proponent of self accountability and responsibility. Put another way, I personally could care less if they were standing 500', 1000' or 2000' away. I'm not the super nit-picky type when it comes to things like that. My thought is that you know the risks if something goes wrong, so use your best judgement.

But since a friend of mine was recently raked over the coals for having people too close, then I just want to make sure that TRA is being consistent with their investigations and dishing it around equally.

SpartaChris said:

The group of people on the left appear to be just on the other side of that same ridgeline?

I guess my point in all of this is that if Andy's project can be scrutinized to death to see if all of the safety code requirements were met, then why shouldn't EVERY project, including this one?

Click to expand...

I could go an and say their at that ridge line and as far back as the tractor appears as well.

I don't have a horse or dog in this race and wasn't there so I'll just stay still about it. Other then if we all start doing this photoanalysis , everyone is going to shoo the photographers away, since it doesn't work unless you have a referance grid.

Nah. Just want to make sure there is some consistency is all.

As an outsider, despite the serious nature of this discussion there is some humor to be seen here. The argument is starting to sound like a bunch of college guys playing quarters...*plink* "Okay, okay, new rule... from now on whenever we have a HPR launch somebody has to put up distance markers like they have at the driving range... drink, drink, DRINK..."

Of course, *I* never played quarters...

I'm far too mature.

Anyways, a VERY long time ago...

(and I am NOT making fun of anybody here this was intended as humor ONLY...)

it's hard to judge distance in photos like this.

It's not much of an issue at our field as there is rarely people behind large rockets when the range is closed. but each club layout works differently.
The RSO has the final say ofcourse.

The bigger the ship the cooler the launch . Too Close? How do you guys think the fella hiding in the payload felt?

Peartree said:

from now on whenever we have a HPR launch somebody has to put up distance markers like they have at the driving range...

Click to expand...

LOL! I made that very same comment at the launch while the
Dragon was being setup. Even with the naked eye and having
walked a good portion of the field recovering rockets (& knowing minor
landmarks), it was difficult to judge the distances. With the camera
lens it is even worse.

Bullpup said:

Should we set the bar at getting the organization insurance canceled? Anything below that we let slide? Seems pretty consistent.

Click to expand...

I'd rather discuss this with you privately, but you don't seem to be set up for e-mail or private chat.

I have some questions, if anyone knows...

Did they make the nose cone themselves, or did they outsource it?

Also, how did they retain the motor?

The aluminum framed construction looks nice- Did they make the fins or the fin cans removable? How did they secure those inside the vehicle?

The fins look like CF. Any ideas what the cores were?

SpartaChris said:

I'm not referring to the tractor.

If you look at this photo:

https://www.ddeville.com/images/Rocket/rocket 187.JPG

and this photo:

https://www.ddeville.com/images/Rocket/rocket 142.JPG

that ridgeline in the background doesn't look all that far away. Maybe a couple hundred feet at most? These are photos taken without the telephoto lens, correct?

And then in this photo:

https://www.ddeville.com/images/Rocket/rocket 186.JPG

The group of people on the left appear to be just on the other side of that same ridgeline?

I guess my point in all of this is that if Andy's project can be scrutinized to death to see if all of the safety code requirements were met, then why shouldn't EVERY project, including this one?

Click to expand...

Do we know where that first photo was taken? That ridgeline seems to extend for QUITE some distance, and it also appears that shot is post-recovery, so who knows where it was taken. I can't find anything besides the ridgeline in the background for reference.

Now, the second and third photos in that post seem to be the key to this. Look at the tractors in the second photo and the third photo. They are all back on that road. In the second photo, that road is QUITE a ways away from the pad. How far? Can't tell for sure, but it seems to be quite a distance. The people beyond the ridgeline in question are standing on that same road, and off to the side, so they are farther away then if you went straight back from the pad to the road (I hated geometry in 9th grade, but I guess I still remember some of it...lol).

We often see photos like this that distort the distances, and I never really understood how much of an effect there was until I saw some pics I took with a strong telephoto lens, and how much it compressed the distances. Really shocking how close things appeared in those shots when I knew they were much farther than they appear in the photos.

Yes, I agree - safety should be scrutinized. The problem is we weren't there, and can only speculate on what happened, what rules were followed, and how they were enforced. Ultimately, it's up to the LCO to determine the flight worthiness of any rocket on his range, and the RSO to determine if the safety conditions are met for those on his range at the time of launch. These are, essentially, the people we entrust our safety to when rockets are sent hurtling to the heavens.

Before the launch, the people there did appear too close to the pad to me. But I was at least 2500', maybe 3000' or more, from the launch pad, so it was difficult to judge distances.

I can tell from looking at my photos that the tractor is larger than a normal tractor (it towered over the pickup when parked behind it). The people in the background of the photo may be standing on the ridge or another high spot, so they may appear taller (and, therefore, closer) than they really were. And, the squashing of apparent distances by telephoto lenses has already been mentioned. So a lot of things can add to the confusion about the distances involved.

Before the launch, it was obvious that those launching the rocket were taking the proper precautions. They set the rocket up very far from the spectators and to the side so that the rocket would not fly over us or drift down over us. The launch was delayed several times for trucks and other farm vehicles in the area and we saw them moving people away from the pad before the launch. So, I have to assume they moved everyone back the appropriate distance.

Anyway, you wouldn't have wanted to be too close to that launch. You would have ended up covered in black mud.

-- Roger

Getting back to the rocket...

What happened to it? And how did it plough that field? Dragged on the chute?

The nosecone chute never opened and it fell into a canal. The rocket floated 3.5 miles away and was dragged by the high through the field. It got a double zipper at deployment and as you can see the aft end had some damage at landing.

Dan

i think i see a second rocket on the grassy knoll.....

Folks, I've had to both give infractions and move a number of threads on this post. I'm closing this thread at this point.

I, personally, don't understand why this thread turned so nasty and why there were a number of people making comments towards one another, but none of those were within the spirit and intent of TRF.