Sunday, February 1, 2015

Launched Three, Lost Three

My fleet has grown smaller.

On Wednesday, Chad and another friend - Jeff - and I launched some rockets. It was going to be either Wednesday or Thursday, but the weather looked bad on Thursday, so we had a small launch window.

Unfortunately, while the winds seemed light, they were stronger than I thought, especially at altitude.

This was my first loss. Losing rockets is an inevitable hazard of rocketry, but this was my first, and man, was it a bummer!

But I learned a couple things on this launch. The first is Check your Go Fever. If the winds look bad, you don't have to launch.

The second is that Chad is a terrible videographer. The footage of the launches is terrible. If my girlfriend had been in town, I'd have some spectacular footage to show you. Fortunately, Jeff got some good pictures.

Chad, as I've reported here before, has lost most of his rockets, and I think he was secretly happy this happened to me. I was actually glad he was there to witness it, so he'd stop whining "Oh, I'm Daniel, and I never lose rockets!"

I'd brought all my bigger rockets, including a few I'd never launched before. Once I noticed it was a little windy, though, I had to make a decision what I was going to try to launch. I was not about to go with the Quest Quadrunner, after all the trouble I'd gone through building it. And replacing it would cost me nearly fifty bucks.

The first loss was the most painful. It was the just-built Cosmic Explorer with an E motor upgrade.

On the left: my original Cosmic Explorer which can only hold up to a C motor.
On the right: the just-completed Cosmic Explorer with an E-sized motor mount -
capable of going three times as high

I knew this was a risk, with a bit of wind. But I'd gotten one of the fins on slightly crooked, and had a little problem with the paint job. And I have two more of them I can build, so I said "screw it! Let's launch this sucker!"

The first thing that happened was that my launch controller wasn't working. I gave it a little shake, and heard some rattling around inside. "That doesn't sound good," Jeff said. I'm not the best at soldering... Fortunately, I had my Estes launch controllers with me. No way to do a cluster launch with that, but I was nervous about those rockets anyway.

The flight was amazing. About 1800 feet or more, straight up. That E9 black powder motor made a huge sound (E is all I've gotten up to at this point, so I'm still impressed by it), lots of smoke, and the thing just soared.

But then, there was no tracking smoke, and after a moment, we lost sight of the rocket completely!

Then, for a second, we caught sight of the parachute. It was so high up and so tiny that I thought it hadn't opened all the way. But it had. 1800 feet might be a low guestimate, and I'm basing it on my OpenRocket simulation. The Cosmic Explorer has a big red parachute, and it was so far away.

After a second, I lost sight of it again. We kept searching the skies for it, and it just vanished. It had headed northwest, but that's all I knew. If it had crashed to the ground, or gotten stuck in a tree, I'd have been sad about that, but the fact that it simply disappeared was... I don't know. I just wanted to know where it had gone.

Sarcasm: Chad reaches out with eyes closed to catch the rocket as it falls straight down...

OK, I knew launching the Cosmic Explorer might be a bad idea. But I decided to keep going. Go Fever.

Next I put the 3D Rocketry Nautilus II on the pad.

This, I thought, would be fine. We have a large flying field, the Nautilus II is fatter and only takes a D motor, and it has a smaller parachute. Besides, it had suffered some major fin damage on its first flight, so I decided to press on with it.

Again, the flight was awesome. Much straighter than the first time I'd launched it, and very high - though not out of sight.

As soon as the chute opened, I thought, oh, no... It's going to go over the trees at the end of the field!

Chad ran to see if he could catch the rocket, which he likes to do. He's like a labrador retriever, and we just can't keep him off the couch...

Then, instead of going over the trees, the Nautilus II landed in the tops of them.

"Rocket-eating trees" are a commonly mentioned hazard in rocketry, and Chad is the Charlie Brown of rockets, but this was my first loss to the trees. And this is a good, open field, so it's not a huge risk here, but it happened.

The only trees to worry about are at the north end of the field.
 Chad ran to see if he could recover the rocket. There it was, tantalizingly dangling from the very end of a thin, outer branch. If the wind changed direction, it might have fallen right out, but the wind was holding the rocket securely on the branch.

I decided to try one last thing. I had the Estes Athena in the bottom of the box. This is a ready-to-fly model I got for $7. I thought If I can get this back, maybe I'll continue launching. If not, I didn't build it, so I won't be sad about it. I tilted the pad slightly into the wind, so that it would fly less high, but possibly come back and land on the field.

All rockets turn somewhat into the wind. For n00bs, this is referred to as "weathercocking." It happens whether you want it to or not. But you can take advantage of it - you can tilt into the wind, and have the rocket return closed to the launch area, or tilt it slightly with the wind, and the rocket will straighten up as it weathercocks, and achieve a higher altitude than it would if launched straight up in windy conditions.

It did weathercock into the wind, and I had hope of getting it back. But the chute opened, and we saw it streak across the sky - the wind must have picked up a lot! It moved so fast, it was like watching Sputnik cross the night sky. It flew over the trees at the end of the field, right over Chad's head, and disappeared.

Chad and Jeff had to leave, and I spent the next hour and a half hiking corn fields looking for the Cosmic Explorer. It had traveled northwest, so I felt I had a good chance of recovering it.

I walked up the hill to the trees and saw the Nautilus II dangling from the branch. I had to cross some train tracks and find a way through the thick brush to the corn field. I walked the whole thing, and up into some grass and woods. Eventually, I realized I shouldn't spend a lot of time hiking around on someone's property, so I hiked back.

I kept thinking I saw it, but it kept turning out to be broken corn stalks gleaming in the falling sun. In any case, I never saw that red chute flutter in the breeze.

Obviously, nothing is green there right now...

I realized that thing could have gone for a mile or two! Or it could have landed somewhere where I couldn't get to or just didn't notice.

I drove around the area, trying to see if I could spot it in an open patch of land. Nothing...

It was only after searching for the Cosmic Explorer that I realized how bummed out I was to lose it. I only got to launch it once, I thought. You can launch any rocket once. The trick is launching it more than once.

I drove back the next day, hopeful that a change in the wind had knocked the Nautilus II from the branch it hung from. Instead, it had become more tangled, and on this day it twisted in the breeze. Today, it's raining pretty hard, so even if it eventually comes down, it will probably be ruined.

So, I lost a few rockets.

But when I got home that night, I started fiddling around with OpenRocket. Out of curiosity, I wanted to see how quickly I could design a little rocket for altitude and speed, using just an E motor and parts I already had. In about twenty minutes, I came up with a design that should top 2600 feet and go Mach .58, or 3500 feet at Mach .61 if I add a D motor booster. I called it Sounder I (for now), and I may lose it, but it was easy and cheap, and it's kind of an experiment. I'm mostly interested in building larger rockets, but I wanted to play around with a simple, high performance design.

I started building it the next day.

Sounder I sustainer, nearly done. I built this in an evening.
I also started building the first scratch design I came up with months ago, a 3-motor cluster called the Trident A.

The Trident A motor mount, part of which will be exposed to view
So, I'm replenishing the fleet.

Like my Facebook page for blog updates.


  1. It's a terrible thing, launch fever. There is no known cure and it results in many calamities such as grass fires, falling out of trees, attacks by guard dogs, electrocution and even the occasional drowning.. The best one can do is "learn to live with it" diabetes.

    At the suggestion of a long time friend, I will sometimes launch an unpainted sacrificial bird just to observe the smoke trail. (An Estes Wizard with a nose blow recovery works well for this.) The winds aloft are often much stronger than at ground level and from a different direction so the smoke trail gives some indicator as what to expect.

    If there are upper level clouds, these can also provide some clue as to what's up there.

    Rocketry and fishing are a lot alike. The trees underwater eat colorful an expensive bass lures and the ones on the land devour my rockets. Trees eat CO2 and black powder motors produce it in copious amounts! Yummy!

    1. I usually do a sounding with a cheap, RTF model first for that very purpose, but I skipped it this time.

      Truth be told, I'm usually surprised they land anywhere near the launch site, ever. Even with low winds, it seems that if they're high enough, a slight drift could take them off the site.

  2. Last time I flew with the Cub Scouts, I told them that the only way to guarantee that you won't lose your rocket is to not fly it. But we built them to fly, so we'll do our best to make sure they came back. One was genuinely upset at the thought that his Wizard might not return... He flew last, after no one else lost theirs. He got his back too.

    1. Funny you should mention that. Turns out I'll be teaching a rocketry camp for kids this summer, and the possibility of losing a rocket is one I'll have to prep them for - especially if we launch on the community college campus where it'll take place. I don't think they have huge spaces.

      I'm trying to push for a launch at the county fairgrounds, just up the road and around the corner - that's a good field at least 1000 feet in any direction. And it would also allow me to have a few "grand finale" launches of some bigger, higher flying rockets - something for the kids (and maybe their parents) to aspire to.

  3. I failed to compliment your friend Jeff for his excellent series of sequential liftoff photos. Well done Jeff!