General Interest

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Aztec Aerodesign Recognizes SEFSD Officers

By Steve Manganelli

The Aztec Aerodesign Club headed by San Diego State University (SDSU) Student Clay Logsdon recognized SEFSD Treasurer Steve Manganelli and Safety Officer Steve Neu at their final club meeting held April 28th, 2023.  Commemorative plaques were presented for mentoring and piloting the aircraft in the 2023 Design/Build/Fly Competition held 2 weeks previously in Tucson AZ.  See last Month’s DBF Article.

The most interesting aspect of the DBF challenge was the wing proof load mission where loads far in excess of what the model could practically experience in the air were designed for and applied in the competition to earn scoring points. The Huizilopochtli model having 55 inch span by 12” chord wing was designed to survive a proof load of nearly 300 lbs, but would it? In competition, our maximum carry was a conservative 155 lbs after some surprising experiments conducted in sunny conditions (hint : West Systems Epoxy and 120 F don’t mix!) but with the competition over, it was time to go for broke…literally. The same mechanism used in competition was deployed (in the shade) with infinite weights available at the Club closing meeting. Each student made their guess as to the final failure weight and wrote it on the test wing.

The custom fabricated wing jointer failed in compression with a loud bang at 274 lbs.! Not sure whom had the closest to the actual, but was an enjoyable time and a fitting experiment to end this year’s DBF challenge. Most of the students participating in DBF this year graduated and are starting their professional careers in aerospace engineering. Myself, Steve Neu and the whole of the SEFSD Club are proud to have support the San Diego State University Aztec community in this endeavor.


Max Dommers, Roberto Marquez and Gabriela Gonzalez look on as wing deflects under weight.  Ms. Gonzalez looks a little worried as she was the one that fabricated the wing joiner!


Clay Logsdon presents Steve Manganelli and Steve Neu Commemorative Plaques. L-R : Jeremy Johnson, Roberto Marquez, Dylan Lake (looking down) Tomas Mendoza, Kevin Garcia, Steve Manganelli, Max Dommers, Clay Logsdon, Magnus Ramsey, Steve Neu, Gabriela Gonzalez

SEFSD Raffle

Attention All SEFSD members!

SEFSD Raffle tickets are now ready to purchase online. Please use the following link to purchase your tickets!

SEFSD Raffle

The purpose of the Raffle is to generate extra funds for our banquet this coming January 12, 2024. The club wants to reduce the cost to club members for the banquet. This raffle goes from April 22, 2023, thru June 30, 2023. Drawing will be held July 1, 2023, down at the flying field. Every club member may purchase tickets. Members do not need to be present to win. Winning tickets, if not present, will be notified by either Certified Mail, Email or a phone call from the information written on the form. Cost of a ticket is $1.00. Members may purchase as many tickets as they wish.
There will be many more exciting prizes but they have yet to be purchased. When they have been, they will be listed in future raffle announcements.
The top prize is the Spektrum iX14 shown below:

CVMRCC Field Cleanup Update

From Tom’s emails on the 21st:

“CVMRCC members & Board,

 Well, the biggest part of the cleanup is done! Sorry I didn’t get this out last night. After a long day out there, I just wanted to get a shower after I got home then send this email, but after the shower I just plain forgot and went to bed.

 So the good news, again, is everything (Well the thick stuff) is cleaned up, end to end. And our bobcat driver, Rockie, did an incredible job not only clearing the runways and pits, but also knocking down the piles of silt and tall weeds around the perimeter of the field.

 We still have some sweeping to do particularly at the far east and west end of the runway, and some in the pits. Robert & I are going to be out there soon today for some of that, though my time is very limited today, and we still also have to fill the bobcat fuel tank back up, too.

 But there’s bad news too. Of course being repeatedly flooded and covered with muddy silt for months is hard on the runway. As careful as we were, the bobcat, and even shoveling and using the blowers on the runway have very easily done damage. From simply peeling off old layers of slurry, to some major pot holes. Repairing the worst parts will be a priority in the near future.

 Thanks to those that showed up to help, including two guys from the Chollas club who came to help! Also a big thanks to John Weaver from Discount Hobbies and Max Younan who’s donations payed for the Bobcat rental.

 So while there might be some sweeping going on today (It would be appreciated if you can help in between flights if you come out today), and unfortunately there’ll be some potholes in the runway to avoid, we can finally get out there and fly!

We’re mostly back to normal now. It’s just tough for the turbine guys now, as the east and west ends of the runway took the biggest beating from the weather. We’re already trying to figure out how to patch the holes.


SEFSD Helps SDSU Aztec Aerodesign Ace Design Build Fly Competition

By Steve Manganelli

Wow, what a ride! 5th place after the first 2 days of competition, then down to 8th near the end of the last day, then up to 6th with a risky proof load and settling out at a respectable 11th out of 99 teams competing. The organizers stated that with over 800 undergraduate Engineering students participating, this was the largest Design-Build-Fly competition ever! San Diego State University Aztec Aerodesign club under the leadership of Henry (Clay) Logsdon made all their practice flights at SEFSD’s Mission Bay Park Field in the days, weeks and months preceding the April Fly off. SEFSD Safety Officer Steve Neu is their pilot and I am their Staff Volunteer Faculty Advisor.

Design Build Fly (DBF), started in 1996 as an American Institution of Aeronautics and Astronautics (AIAA) sanctioned annual competition for undergraduate Aerospace Engineering college student teams. The basic challenge is to design, then build, then fly an electric powered R/C model optimized for specific cargo missions that change every year. The course has always been the same 1000 ft oval with an opposite direction turn on the downwind leg. Myself and Steve Neu’s first involvement was in 1999 when UCSD student Andrew Mye came to an SEFSD evening members meeting and requested help/expertise in the somewhat novel at the time, discipline of electric powered R/C modeling. Andrew and his team of (4) placed 6th at our first try at the event with about 30 teams participating; Steve Neu and I subsequently guided UCSD to (4) additional top 10 finishes and the win in 2002. UCSD changed to a faculty guided methodology and Steve Neu and I migrated to SDSU in 2019. The event has gotten more and more prestigious over the years and international with at least (18) schools from abroad competing in this year’s competition.

DBF entry begins with submittal of a 5 page proposal of how a team intends to meet the mission requirements. This year, (135) proposals were submitted and the best 110 were invited to participate in the competition. Ninety nine submitted the required 60 page Report detailing their analysis and methodology leading to their final design making them eligible to compete in the flyoff April 13th through 17th.  The flyoff location alternates between Tucson with Raytheon as the primary sponsor and Wichita KS with Cessna as the primary sponsor. This year’s fly off was held at the TIMPA R/C airfield in Tucson AZ. Our Aztecs’ proposal and report were ranked 25th and 29th respectively so starting in November, 2022 the adventure began.

The proposal passing muster triggered the actual aircraft design effort based on mission optimization and the scoring formula. Three of the (4) missions used normalized scoring where the school performing best at each mission gets a factor of 1 and everyone else gets a fraction of that number based on their score relative to the winner’s. It’s a bit nerve wracking as every time a new best is posted, all the existing scores go down; the written report score is a multiplier for every mission. The most intriguing mission this year was a static proofload of the center of the fuselage supported by the wing tips. This is not representative of an actual flight loading condition where the load occurs more or less uniformly along the wingspan. Simply supporting the aircraft by the wing tips is approximately a 2.5G flight load. Imagine then, what adding 150 lbs to the center of the fuselage while supported by the wing tips might be? That’s what our Aztecs did and still only garnered a 0.47 because the German team carried….wait for it, 750 lbs! I didn’t see how a single German student wrestled the 750 lbs of 12 X 12 concrete pavers in around 5 minutes but our clever Aztecs used an automotive floor jack to lift their exercise weights into position.

The German team from RWTH Aachen University built a wing with anhedral and their loading fixture kind of “post-tensioned” it as it was loaded allowing it to carry more weight not unlike a masonry arched bridge where the loading components are in compression.

The next most interesting aspect of the mission is each one had to start from the aircraft in an airline baggage legal size container and be assembled ready for flight by one Student in less than 5 minutes or less than 10 minutes when the static proofload was part of the Mission. Our creative Aztecs designed a pod and square boom fuselage where the boom retracted into the fuselage up to the firewall and then locked when deployed with a typical canopy latch. Wires to the elevator and rudder servos stayed connected to the RX during all conditions. The next obstacle set forth by the organizers is the requirement to have 2 interchangeable sets of wings. Two coin flips just before your turn to fly selected the left and right panel from the set of (2) which both had to fit into that same airline size box. Master assembler of our team Max Dommers, calmly withdrew the 4 wings from the box and set them aside, then pulled out the fuselage and extended the tail boom. The MLG was attached with (2) thumb screws and then the fuselage set on it’s wheels. Next the wing joiner was installed into the appropriate wing and then slid into the fuselage, the other wing was next slid on and the two held inboard with a rubber band. The aileron wires were next connected and the motor battery was installed. Lastly, the prop adapter and prop were installed. Max had this down to about 3 minutes which was necessary as the other normalized missions added installation of a payload to the 5 minutes!

The intermediate payload was a weight having dimensions at least 3” X 3” X 6”, amount of the teams choosing however the mission score depended on the product of the payload weight and the number of laps that could be flown around the course in 10 minutes. Steve Neu expertly piloted “Huitzilopochtli” (Aztec Left Hummingbird God) (12) laps around  the course in the allotted time and put a nice score on the board for us.

The final heinous mission was to carry a simulated jamming antenna in the form of ½ inch schedule 40 PVC pipe, the length of the teams choosing as long as it fit into the box. Oh yeah, it had to be carried on the wing tip toward the inboard side of the course! The teams were allowed a counter weight on the opposite wing tip but not a “counter drag” the pilot simply had to deal with it. Both pipe and counter weight had to be installed within the 5 minutes. Max expertly put it together in under 5 minutes and Steve Neu expertly piloted Huitzilopochtli around the course for 3 laps in about 2 minutes carrying a 24” inch (pipe) antenna.

At the end of the flight, he pronounced the aircraft too tail heavy and pitch unstable to risk more points with a larger length pipe and the decision was made to save the plane for the proof load mission. Our first successful proof load of 85 #s kept us in 8th place but Max calculated that 150 (which is more than we’d ever tried) would put us up to 6th place! The go-for-broke (literally) load was successful and we moved up. All we had to do was wait out the teams yet to fly after us and hope none of them did anything better than us. Of course those immediately below us tried to do the same thing and (3) teams overtook us. Embry-Riddle-Prescott whom was missing a mission score late in the contest zoomed up to 7th from 25th once they completed their pipe/antenna flight. The clock timed out and we happily took our well deserved 11th place finish. Congratulations to 1st Place RWTH University Aachen (Germany), 2nd Place University of Ljubljani (Slovenia) and 3rd place Embry Riddle Daytona Beach Campus. For detailed results and more information, go here : AIAA Design/Build/Fly | AIAA .   All in all a cherished opportunity for SEFSD to support our future Aerospace Engineers.

Click here for the full album of pictures.

One Gloomy Picture

This is the only pic I got from our photographer Frank this month.  Either Frank was sick or the event was rained out.  It shows a dark full overcast, South wind, puddles, mud everywhere and not one flyer.  That pretty much sums up the month.  We hope this weekend is a lot dryer.

Safety & Security

One of the most important rules the city makes us enforce is controlling access to our area by means of the gate with a pad lock. The general gate protocol is as follows:

1) The first member entering the area will open (the combo is on the back of your membership badge) the lock and push the gate open and then spin the numbers on the lock  and latch it closed so it can’t be removed easily by a passerby.

2) If you are the last member leaving the field first check and inform any people with cars that they need to leave because the gate will be locked shortly. Once the area is clear,  exit and close the gate behind you and then lock and secure gate closed with the chain and lock—make sure it is locked! Spin the numbers!

Steve Neu

Founder’s Trophy – Dennis Laberge

The Founder’s Trophy was introduced for the first time this year at the Holiday Banquet.  This trophy will be given annually to someone in the club who has demonstrated selfless contribution of time and talent well beyond the call.  No surprise it was given to Dennis LaBerge for his dedication to the care and maintenance of our field.  Please congratulate Dennis next time you see him.

And the Award Goes to. . .

By Steve Manganelli

Those not at the banquet and those not involved with T-28 racing missed out on award presentations to two of our Club Heros. Let me back up a bit to Fall of 2022 where the BOD voted to create a perpetual award to be handed out at the Banquet to a non-BOD member making the greatest contribution to the operation of the Club during the previous year. I coined the name “Founders Trophy” the intent being that it will presented by one of the original founding members of the Club to convey our appreciation.

At the banquet, I was most pleased to be able to present the trophy to Mr. Dennis LaBerge whose contributions toward maintaining the field are innumerable and exemplary: Thanks so much Dennis! Dennis also received a plaque commemorating the occasion which is his forever, but the Cup/Trophy he has to surrender at the 2024 banquet to be awarded to the member making the greatest contribution in 2023. Who’s that going to be, you?

Those at the banquet were privy to Frank Sutton’s pictorial essay of our previous year thus know what a great photographer he is, but did you know he does medals too? A couple of year ago, it was decided that “cheesy” medals would be a appropriate recognition  for T-28 racing Gold-Silver-Bronze Cup winners. Then later, I discovered that a custom picture insert could be included for only a little more money and I of course turned to Frank for the artwork. For this year, we decided that a T-28 appearing to be hitting a pylon and a tree was the perfect homage to T-28 racing.  Below is me presenting the first 2023 T-28 to it’s artist, Mr. Frank Sutton. Thanks for all your hard work, Frank!