Super Big Bertha for L1 attempt?

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Charlie4N

Charlie4N

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Hello everyone!

I am thinking about going for my L1 cert this summer. I've been looking at different kits and recommendations and I will probably end up going with something like the LOC IV or one of the other popular L1 kits. However, I absolutely love the Bertha's and was wondering if the super would make a good kit for L1.
 
I would really stick with a 4"in. rocket and remember the LOC Goblin which can use 29mm, 38mm, and 54mm motors and almost everything comes in the kit. The only items I recommend for the LOC Goblin are a Jolly Logic Chute Release and a nomex shock cord protector. I use electrical tape to keep the shock cord protector in place.
 
Here's my best certification advice. Find a utility design. Nike Smoke. done. (change the nosecone if you want to be really different.......) Keep all cert launches below 5000ft. Cloud comes in at about that level and you'll still be able to do your cert if it gets cloudy. That way you can get all your certs out of the way and have fun. And you should only have to do the paperwork once.
Having said that, that's not how I did it, but I wish someone had at least said this so I knew I'd have to take 3 launch attendances to remote locations at a cost of thousands of dollars to get a window to be able to launch for the cert flights.
 
RocketScientistAustralia said:
Big Bertha has rearward fins. If you break a fin, you fail L1. BAD design for a cert attempt.
Click to expand...

BuckRogers said:
Valid point -- especially with the stock balsa fins! I built mine with plywood fins, but there's a lot of fin hanging behind begging for damage on a cert flight.
Click to expand...
A very valid point.
RocketScientistAustralia said:
Here's my best certification advice. Find a utility design. Nike Smoke. done. (change the nosecone if you want to be really different.......) Keep all cert launches below 5000ft. Cloud comes in at about that level and you'll still be able to do your cert if it gets cloudy. That way you can get all your certs out of the way and have fun. And you should only have to do the paperwork once.
Having said that, that's not how I did it, but I wish someone had at least said this so I knew I'd have to take 3 launch attendances to remote locations at a cost of thousands of dollars to get a window to be able to launch for the cert flights.
Click to expand...
looks like some good advice to me. I guess I'll save an upscaled bertha for a post cert project
 
Could you do a cert flight on a modded SBB? Sure. Should you? That’s a whole ‘nother question. It’s going to really get up there on even a lower end H and the plywood fins, though stronger, are still vulnerable to damage. Others made some good recommendations for L1 certification rockets - I did mine on a heavy, draggy 4” crayon rocket with a JLCR and it worked perfectly, just like my G powered practice flights, just slightly higher.

But I’ve also watched a guy do his with a 3” rocket, full dual deploy, on a big H and it was a complete success. I think he flew close to the waver limit! The caveat to that is he flew that rocket (and similar ones) multiple times on F and G motors and picked a day with very calm winds.

So if you’re comfortable flying high and fast, have plenty of experience doing it and take the necessary steps to minimize potential problems, a well planned cert flight of a SBB could work fine. Personally I wouldn’t do it but that’s me - if it’s your kind of groove go for it!
 
RocketScientistAustralia said:
Big Bertha has rearward fins. If you break a fin, you fail L1. BAD design for a cert attempt.
Click to expand...
And you have to recover it. It would go very high, out of sight. It would only be feasible with an apogee deployment (mine has an Eggtimer Apogee in the nose cone), a tracker Eggfinder Mini or Featherweight GPS in a Lab Rat Rocketry sleeve, and a chute release. You would also probably want to upgrade the fins to plywood, make them TTW, and use epoxy, to avoid a fin flutter failure possibility). It would have to be a baby H (H100W) to keep the speed down. That's a lot of gear for a simple L1....
 
No Joke - John Buckley did his L1 on a Big Bertha on an OG AT H124J. Got it back on the first try, too. Not sure if he ever flew it again. I have a BB kit I might mod into 29mm for SnG's.
 
cls said:
... With the same rocket.

I really wish people wouldn't do this.

What are you saving? Cost of a second rocket. What are you missing? A lot of learning.
Click to expand...

I agree. I am not a fan of the L2/3 rush. There is a lot to be done, a lot of fun to be had, and a lot to learn as an L1. Even more so as an L2.

Just my $0.08
 
When I was asking around on what rocket to use I kept getting the same three recommendations. The first was the Apogee Zephyr and the other two were from LOC, The Warlock and the 7.5 Magg.

I initially bought the Zephyr but after seeing one fly for a cert flight I decided it wasn't what I wanted due to altitude. I then spoke to LOC they said absolutely go with the Warlock. Crazy strong and has the aerodynamics of a barn door. Doing some research I found that an H550 will put the Warlock up around 600-650 ft. at my weight. If I can find some black powder for the ejection, I'm hoping to get my level 1 this summer.

Here are a couple of videos that finally convinced me.



 
A fat, heavy rocket is good for L1 since it doesn't go high and simple motor deploy works.

I'm going with the LOC 4" Goblin for L1 (in a few weeks) since I can fly it on G's as a Class 1 (under 1500 grams) at local field. This sims to 900' with an H238 (or H128 or H165). On a G76G it goes to about 500'.

If you can get to HP launches then bigger is better. An H for the L1 and bigger H's thru I's later.
But if your local club is only Low and mid power than consider something you can fly under 1500 gram on G's.
 
waltr said:
A fat, heavy rocket is good for L1 since it doesn't go high and simple motor deploy works.

I'm going with the LOC 4" Goblin for L1 (in a few weeks) since I can fly it on G's as a Class 1 (under 1500 grams) at local field. This sims to 900' with an H238 (or H128 or H165). On a G76G it goes to about 500'.

If you can get to HP launches then bigger is better. An H for the L1 and bigger H's thru I's later.
But if your local club is only Low and mid power than consider something you can fly under 1500 gram on G's.
Click to expand...
I've flown mine on H182R, J381SK, many H182Rs, and I170G. This is a great rocket!
 
Last edited:
Needs to be an H for L1 certification. G88 is classified as HP because it has over 80N average thrust. This does not make it a motor that can be used for HP certification although it requires HP certification to be able to use it.
 
Just commenting on my scratch built SBB! Altitude!!!!
 

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