Motor selection for my level 1!

[RocketSquirrel]

Hi everyone! I've finally got the LOC IV finished minus the paint. I have narrowed my engine down to the H135 based on available local inventory. The total mass w/o motors is 1108g, with is 1230g. Apogee is 680m and about 11 seconds to get there. I ran a simulation and things look smooth, hopefully im using OpenRocket correctly! Looks like ill need to shave a couple seconds off the delay, the computer is saying optimum delay is about 9 seconds.

I really just wanted some reassurance, I've learned a lot in the last two months working on my first high power rocket! I'm so scared something will go wrong but that's part of the fun.

 

[tsmith1315]

I'm so scared something will go wrong but that's part of the fun.

Indeed!

Keep in mind that motor ejection delay time is an approximate value, no need to obsess over it. With +/- 20% tolerance, anything within a second or two (or three) is considered to be correct.

I’d use the OR prediction of optimum delay for adjusting it and let ‘er rip!

Be sure your rail length is correct in the sim for an accurate velocity off the rail.

Otherwise, think of it as a Big Estes Alpha and enjoy your day!

 

[Rob Campbell]

I certified on a Zephyr flying on an H123, which is a similar combination to your Loc IV on an H-135. I use an 8 second delay, so your predicted apogee and 9 second delay sound reasonable.

 

[Handeman]

I've been flying a 2.6" diameter 2 lbs. rocket on H180W motors, which is almost the same as the H135W SU. I get 3000 ft. from that. With your 4" diameter LOC IV, the 2000 ft. is about right.

 

[Buzzard]

Are you planning to fly with DARS in Gunter on the 21st? I have a JLCR if you would like to see it and consider using it .

Chas

 

[RocketSquirrel]

Are you planning to fly with DARS in Gunter on the 21st? I have a JLCR if you would like to see it and consider using it .

Chas

I will be there!! Its nice to meet someone that planning on being there too. I actually have a JLCR, i havent used it and i figured its one more thing that can go wrong on a cert flight. You can maybe talk me into using it, im just confident in what i know so far.

 

[Buzzard]

I would be happy to share my experiences with you and try to demonstrate the JLCR prior to your attempt. As one of the gray beards of DARS, I may be one of the first to have to pull a range shift. Look for the old guy in the Ohio State shirt...

C

 

[RocketSquirrel]

Sounds awesome! Im the 35 year old guy with long hair. You go by Chas? I'm Johnny! Whats it mean to "pull a range shift"? Hopefully I'll eventually be a gray beard with DARS and ill find out first hand haha

 

[Buzzard]

There are several jobs that need to be done to make a launch successful. The Range Safety Officer (RSO) is on the launch controllers and is responsible for airspace clearance and launches. Safety Check is the first line to ensure that the rocket a modeler presents is safe and has been prepped correctly (motor retained, wadding, recovery device), the Pad Managers assist the modelers in putting their rockets on the pads (correct rod or rail, microclip hookup, assisting kids in putting their rocket on the pad), and MOST important of all are our Registration Tent Personnel. The latter signs up the High Power flyers, helping new members join DARS, are timers for the America Rocketry Challenge, etc. Be nice to Suzy, Jada, and Cindy. (yes, I am sucking up to them).
A short synopsis of the range duties, but volunteers usually sign up for one hour shifts and the flying can go on hold if certain positions are not filled. Many flyers do not understand or appreciate the efforts to set up the range, run the range, and the tear down of the range. The average age of the club officers and volunteers is around 60. Please observe all signs and safety rules. Make sure that you have water. When the range runs smoothly then everyone gets to fly. After all, we are there to fly our rockets, too.

Chas
Charles

 

[ShadowSpire48]

One thing that I was told by multiple people when I was looking to do my L1 is to keep certs simple and just stick to DMS motors so the H135 will be perfect for your flight. I did an H115 on my L1 and a J425 on my L2.

 

[RocketSquirrel]

There are several jobs that need to be done to make a launch successful. The Range Safety Officer (RSO) is on the launch controllers and is responsible for airspace clearance and launches. Safety Check is the first line to ensure that the rocket a modeler presents is safe and has been prepped correctly (motor retained, wadding, recovery device), the Pad Managers assist the modelers in putting their rockets on the pads (correct rod or rail, microclip hookup, assisting kids in putting their rocket on the pad), and MOST important of all are our Registration Tent Personnel. The latter signs up the High Power flyers, helping new members join DARS, are timers for the America Rocketry Challenge, etc. Be nice to Suzy, Jada, and Cindy. (yes, I am sucking up to them).
A short synopsis of the range duties, but volunteers usually sign up for one hour shifts and the flying can go on hold if certain positions are not filled. Many flyers do not understand or appreciate the efforts to set up the range, run the range, and the tear down of the range. The average age of the club officers and volunteers is around 60. Please observe all signs and safety rules. Make sure that you have water. When the range runs smoothly then everyone gets to fly. After all, we are there to fly our rockets, too.

Chas
Charles

Good to know, id like to volunteer if help is needed throughout the day.

 

[bad_idea]

Good to know, id like to volunteer if help is needed throughout the day.

Even aside from range duty, help is always appreciated for setup and teardown. I nearly never make it to the field in time to help with setup, so I try to stay to help with teardown.

 

[RocketSquirrel]

Even aside from range duty, help is always appreciated for setup and teardown. I nearly never make it to the field in time to help with setup, so I try to stay to help with teardown.

How early does everyone get there? Im bringing my wife and father in law, if i can get everyone out the door for the 45 minute drive ill be there! If not help as needed. When we get closer do they announce more information? I dont mean to turn this into a long winded novel, i could sit here and ask questions all day! Haha

 

[bad_idea]

How early does everyone get there? Im bringing my wife and father in law, if i can get everyone out the door for the 45 minute drive ill be there! If not help as needed. When we get closer do they announce more information? I dont mean to turn this into a long winded novel, i could sit here and ask questions all day! Haha

Setup is generally in the hour before the official start time. This month's launch should start at 10, so setup probably at 9.

Join this group and set up your email, and you'll get any updates as they come:

https://groups.nar.org/g/DallasAreaRocketSociety

 

[samb]

Honestly @RocketSquirrel all you want to do is relax , breathe , and cert L1. Setup, teardown, and range duty can wait for another day.

 

[samb]

Other than all the info you got from George via email, the only thing left is a go/no go decision usually by Wednesday the week of.

 

[bjphoenix]

Hi everyone! I've finally got the LOC IV finished minus the paint. I have narrowed my engine down to the H135

I did L1 with a rocket that size using an H123 so you are in the same ballpark.