Archive for Daniel Cavender

HARA Newsletter – April 2013

Houston, We have a Problem” ~ Apollo 13 – April 13, 1971

 

At the last HARA meeting, Walt Stafford, our resident expert composites and XP motor maker brought in some samples of his fiberglass airframes and nosecones as a primmer for the composites workshop we had of April 6th. Read more

HARA Newsletter – March 2013

Test what you fly, and fly what you test”

Thursday night’s meeting was another success.  Attendance has been up 3 fold and the new focus of the meetings on helping people grow in hobby rocketry and show off their projects seems to be resonating rather well.  I gave a 45 minute presentation on dual deployment recovery systems in our first in a series of Tech Talks that cover lots rocket building techniques.   Read more

HARA Newsletter – Feb 2013

“We Are On Ascent” ~ Vince Huegele

 

Thank you everyone for coming to the meeting last night. We had a great turn out with nearly 30 people in attendance and a lot of new faces. We kicked off the meeting with our guest speaker and a few pizzas.  Mr. Chuck Pierce who is branch chief of Spacecraft Propulsion Systems at MSFC and has a rich background with space shuttle and hypergolic propulsion systems, shared with us the propulsion research being done here in Huntsville.  Mr. Pierce brought along a space shuttle reaction control motor to show off. Read more

HARA Newsletter – Jan 2013

Greetings members and friends. First, thank you Ray for your years of service as HARA President. Secondly, thank you David, Bill, Josh, Vince, and Fred for volunteering as officers for 2013. We are already hard at work preparing for the upcoming flying season. I want to share some news with you from the Officers. Read more

Product Review: LG Keychain Alarm / Adept SB1 Sonic Beacon

by Daniel Cavender

Last year, the field at Manchester, TN was planted half in sod and half in corn posing certain logistical challenges regarding recovery. There were several rockets that were lost in the tall corn and never recovered. One rocket made its way into an unfortunate combine and did significant damage. That issue is being resolved, and to our benefit, the field is all sod this year. HARA is implementing some new range safety practices to mitigate any further such incidents, but good launch site stewardship is the responsibility of every flyer. All flyers with rockets built using fiberglass, metallic, and other dense materials may be asked to outfit their rocket with a sonic beacon (if not already equipped with GPS or radio beacon). To help flyers find these beacons, this product review will examine two products: the LG personal security keychain alarm, and the Adept SB1 sonic beacon.

LG Personal Security Keychain Alarm

The LG keychain alarm is a very cheap and very loud device that can be quickly pressed into service as a sonic rocket recovery beacon. The alarm needs to be taped to the shock chord. The trigger device is a pull pin that takes about 2 lbs of force to trigger. HARA President, Ray Cole, flew one of these beacons at the March launch and it worked great. They were on sale for $4.95 at Lowes. The batteries are replaceable and the case is robust and provides protection from moisture and BP residue. At $4.95, this is a piece of insurance that will pay for itself time and time again.

Adept SB1 Sonic Locator Beacon

The SB1 is a small 90 dB sonic beacon designed for rockets. It can fit in the body tube of a 29mm rocket. The trigger device is a jumper tied to the shock cord that pulls off of two wires on the back of the SB1.The SB1 needs to be taped to the shock cord against the trigger and jumper. This is a poor design and did not work too well in the field. The jumper fell off easily during packing. The open unit made it prone to damage from the littlest amount of moisture or BP residue. Compared to the $5 option from a hardware store, the SB1 did not hold up.

Product Review: Perfectflite Stratologger SL-100

by Daniel Cavender


The Perfectflite Stratologger combines the best features of the MAWD and HiAlt45, and offers greater programmability, data storage, and reliability. Those familiar with both the MAWD and HiAlt45 will have an easy time transitioning to the SL100. The SL100 is the same size, and has the same mounting holes pattern as the HiAlt45. The SL100 can operate up to 100,000’ MSL, and temperatures approaching -40°F. The SL100 records, altitude, temperature, and battery voltage at 20Hz for 9 minutes a flight, and can store flight data for 31 flights (> 55 times the MAWD). The SL100 has a telemetry output for real-time data in flight with your RF link. Precision sensor & 24 bit ADC yield superb 0.1% altitude accuracy (5 times the MAWD). The SL100 incorporates a post flight locator siren to aid in locating your rocket. An auxiliary output allows you to install an amplified external beeper.

At start up, the SL100 reports currently selected program preset, main parachute deployment altitude, previous flight apogee, and lastly, battery voltage, then lastly continuity by beeps.

The Stratologger seems a superior altimeter and at $20 cheaper than the MAWDs, which are now discontinued, it seems a good bargain for the capabilities. Thanks to the Perfectflite team for again building a quality, reliable, affordable altimeter.