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Category: Archive 2014

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1. Santa's Toy
2. Lost Hills Info
3. Fab Feb Flyers
4. Box Rubber for sale

Jim Parker – Santa's Toy and Pin turbs...

Editors note - we were going to include in this issue flyers for all 3 Fab Feb World Cup events but pushed the Ike/Kiwi out to the next issue because of this article.  SCAT member Jim Parker posted info on FB about his new F1A.  This drew a number of interesting comments, in particular from Tony Mathews and Brian Eggleston.  We publish below a slightly edited version of this FB conversation and include some additional words of wisdom from Jim's other advisors : the Squatter and the Leeper .

Jim Parker: Santa finally delivered the new F1A ! First flights Jan 1, 2014--Lost Hills. Used my LDA program with a .65 sec shorter cruise time. Had to RDT first flight- launched to left and stalled. Moved all rudder to right and dropped stab one count (3.2 deg, airfoil bottom lines-- ie not true incidence) and nail flight 2. no altimeter. Ten or so flights- lovely weather and time with Shlomi and Peter A.

This is the specs of the new model :

Pushed the wing back on the M&K fuselage pod to lengthen the nose / minimize nose weight. The wing bottom is as low to the hatch line as possible and the TE slightly above the fuselage. Model is the Shlomi Hybrid airfoil wings by Milhaly Vardi with M&K mechanics and impulse hook and a Black Magic VR 4/5 servo timer. 

Also, variation on theme of Ken Bauer pin tabulators. Think I'll try it on one of my standard M&K long models.

Mike McKeever : So what is it? Santa actually knew your colors...so you have that going for you! See you soon in LH with your new toy.

Tony Mathews: I like the turbulators Jim. Shlomi said your new bird trimmed out fast and that you liked it.

Jim Parker Tony-- Shlomi also informed me that you designed the hybrid airfoil and should be credited-- Thanks!

Tony Mathews : Jim, I've been meaning to complete an article about this for the Digest. It's a bit more complicated. Other than Roland Koglot, 2 years ago nobody felt that LDA models (F1A) were suitable for "rounds" models. I originally asked Brian Eggleston to design a windy weather/thermal LDA airfoil that would behave on the line and glide like a Benedek. He wasn't too enthused at the time as he was busy with other projects. So I took a Benedek 6356b upper surface, and added an LDA lower surface, created coordinates and emailed them to BE. Then Peter Allnutt and I showed up at his house asking if he could "help" me/us run the airfoil through xfoil to see how it performed. He opened the coordinates, took one look at my lower surface pressure distribution and said "no, no, that's not right at all". Then proceeded to redesign the lower surface until it matched what he felt the pressure distribution should look like for an F1A LDA and Viola! The Benedek/LDA hybrid airfoil was born! Btw, there have been a few "tweeked" versions since then done by Brian that have not been tried. 
I then drew up a short wing F1A design using this airfoil, (based on the M&K short wing) and sent the plans and coordinates to Mihaly Varadi to build. Jama Danier received the first set of wings (he used them to win the 2013 US Nats in turbulent difficult conditions), and Mihaly has made many sets since (including Shlomi's and yours etc).
So I give Brian credit for the airfoil work, and take the credit for the wing/model design.
It looks like Whobby have used my drawing to create a short model that they sell now, so it goes on...

Lee Hines: Tony&Jim, that about conforms to what I heard re this LDA section & planform. Also that RoKog did very much the same for his successful rounds LDA. An article on such will be welcomed.

Hernan Alarcon Herrera Jim Parker, is very interesting for me the test in M&k and others airfoils with this turbulator. Please send me basic information about this. Thank you very much.

Brian Eggleston  : FYI here's a description of pin turbulators and how they work along with a reference:

From: Turbulator Alternatives for F1A Airfoils 
42nd Annual Report NFFS Sympo 2009

Pin Turbulators
The vertical “Pin” turbulators are small cylinders projecting normal to the wing surface, typically at about 5% of chord, see ref. 12. The pin diameters are sized to shed a Karman vortex street for glide speeds that give pin RNs in the range 100 to 200.

Fig 17. Pin Turbulator Concept*

The train of regular alternating vortices is much more energetic than the random, turbulent wake that is shed at higher RNs. Typical values for pin diameters are about 1 mm and pin lengths are about 1 to 1.4 mm. 

The lateral spacing of the pins is set so their trailing wakes spread and merge ahead of the bubble to promote earlier transition. Relative to a bluff continuous turbulator the total frontal area of the pins is about 70% less, so a major reduction can be expected in the turbulator’s own drag contribution. 

During tow the airfoil surface between the pins will experience wedges of laminar flow which will lead to further drag reduction relative to fully turbulent flow behind a continuous turbulator. The net effect on drag cannot be reliably estimated but it should fall roughly midway between clean (L/D = 92) and turbulated (L/D = 64.5) values.

12. Hobinger R., “The Pin Turbulator”, 37th Annual Report NFFS Symposium, 2004

Brian Eggleston This may attach the missing figure ( Brian put a picture on FB – to see it you need to get the sympo he refers to or go to FB)

Hernan Alarcon Herrera Thank you.

Tom Coussens There you go, pard, knew you'd eventually catch on to "Arbitrary Trim" - make all adjustments at once, git 'er done!

LOST HILLS FREE FLIGHT MODEL AIRFIELD ASSOCIATION

It is once again time to renew our membership to the LHFFMAA. After consideration by the Board the basic dues for 2014 will remain at $20/year, however to renew for $20 you must send your renewal form and check in by January 15, 2014. Because quite a few flyers did not register by mail prior to last year’s Isaacson’s Winter Classic, the first contest of the year, there was a sizable bottleneck at the sign-in table caused by on-field renewals which placed an undue burden on the CD running the contest.

On-field renewals throughout the year and the subsequent continual need to update AMA records is another really time consuming job. Therefore in order to encourage early membership renewal, all renewals made after January 15, 2014 and all renewals made on the field will be $25. The two year discount renewal is still $35, except, as noted, if it is made after January 15, 2014 or made on the field; then it will revert to $40/2 years ($25 + $15).

Juniors 16 years old and under will receive free Lost Hills membership. However, juniors must be a member of AMA.

There is also a yearly family discount rate for two adults living in the same house for $35. The family discount for two years is $65 ($35 + $30). The family discount after January 15^th or made on the field for two years is $80 ($50 + $30).

There is no penalty for first time members or for flyers from a foreign country.

For special events a $10.00 use fee per person, which is good for a two-week membership.

Note: Quite a few members paid for two years last year so don’t send dues if you have already paid for 2013.

Make checks payable to LHFFMAA and mail to:

Brian VanNest

2346 Cheyenne Drive

Bishop, CA 93514

Email: This email address is being protected from spambots. You need JavaScript enabled to view it.

Fab Feb Info - reminder 

2014 MAXMEN INTERNATIONAL

A World Cup and America’s Cup Event

DATE:                        Feb. 13-17 ,2014

PLACE:                      Bissonette Mirage Field, Lost Hills, Ca. USA

SCHEDULE:                  - F1E   Thursday, Feb. 13th (organized & run by SCAT)

- F1A    Friday, Feb. 14th (7 rounds + flyoffs)

- F1B, C and P Sat., Feb 15th (7 rounds + flyoffs)

                                                7 rds each day, starting at 8 am, 1 hour rds for A,B,C, P

                                                1^st. round extended max per FAI SC for A,B,C

                                    - F1G, H, J and Q Sunday, Feb. 16th

                                                5 rds. 1 hr each starting at 8 am for G, H, J

                                                7 rds, 1 hr each starting at 8 am for Q

                                    - Reserve day, Monday Feb. 17th

SPECIAL NOTES:          - FAI Sporting License is mandatory for all competitors flying F1A, B, C, E, P, Q

- US competitors can mail entry form, with fees to CD (email entries from US flyers will not be accepted)

- Non US competitors may email entry and pay upon arrival

- All non-AMA competitors must pay $28 AMA Affiliation fee

- Competitors MUST provide their own timekeepers. Two timekeepers per competitor are required for the flyoffs.

Fly-off times will be decided on the day depending on the weather.

COST:                          F1G, H, J                      $15 / event

                                    F1A, B, C, P and Q       $30 / event  ($15 for Q if combined with F1A,B,C or P)

                                    Junior competitors fly FREE!!!

CONTACT:                   Marty Schroedter

                                    807 Inverness Dr. Milpitas, CA. 95035 USA

                                    Ph. 408 829-5477 Fax  408 263-4524

                                    Email: This email address is being protected from spambots. You need JavaScript enabled to view it.

LOCAL MOTELS:          Lost Hills Motel 6        661-797-2346

                                    Lost Hills Days Inn       661-797-2371

AMERICA’S CUP BANQUET

DATE: & nbsp;                                  Feb. 15, 2014

PLACE:                      Wasco Elks Club

PROGRAM:               Dinner and America’s Cup Awards presentation

COST:                         $21.00 for adults, $16.00 for Juniors

2014 MAXMEN INTERNATIONAL & A C BANQUET ENTRY FORM

NAME___________________________________________________________________________

ADDRESS________________________________________________________________________

CITY, STATE, ZIP_______________________________________________________________

FAI LICENSE NUMBER_________________________________________________________

PLEASE ENTER ME IN:

          F1A ($30)                                ______________________________

          F1B ($30)                                ______________________________

          F1C ($30)                                ______________________________

          F1P ($30)                                ______________________________

          F1Q ($30/15)                           ______________________________

          F1G ($15)                                ______________________________

          F1H ($15)                                ______________________________

          F1J ($15)                                 ______________________________

          TOTALENCLOSED               ______________________________

          ALL JUNIORS FLY FREE, BUT MUST PRE-ENTER

          BANQUET ($21)                    ______________________________

          BANQUET under 17 ($16)     ______________________________

***CONTESTANT MUST PICK UP CONTESTANT’S PACKET AT CD TENT BEFORE THE 1^ST ROUND OF THEIR EVENT OR SCORES WILL NOT COUNT

SEND ENTRIES TO: Marty Schroedter (This email address is being protected from spambots. You need JavaScript enabled to view it.)                                    

807 Inverness Dr. Milpitas, CA. 95035                                 

The Toronto Free Flight Group

Presents the 2014

North American Cup

A World and America's Cup FF Competition

Dates: Tuesday, February 11th 2014 with Wednesday February 12th as reserve day

Place: Bissonette Mirage Field, Lost Hills, CA USA

Events: Individual F1A, F1B, F1C, 3 Person Team F1A, B & C (Teams can be mixed nationalities)

Entry Fees: $25.00 for F1A, F1B, F1C – Team entry included in fee

Juniors free all events!

AMA liaison CD: Hector Diez

Co-Organizer: Peter Allnutt: 527 Philippine St, Taft CA USA (661) 763-5039

Organizer: Tony Mathews: 2 Tralee Street, Brampton, Ontario, Canada L6Z 2X4

cell: +1(705) 754-5553 E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Tuesday February 11th

F1A/B/C Round 1 8:00 am – 9:00 am Rnd 1: 210 sec max F1A, 240 sec max F1B/C

Round 2 9:00 am – 10:00 am

Round 3 10:00 am – 11:00 pm 180 sec all other rounds

Round 4 11:00 am – 12:00 pm

Round 5 12:00 pm – 1:00 pm

Round 6 1:00 pm – 2:00 pm

Round 7 2:00 pm – 3:00 pm

F1A/B/C Fly-offs 3:30 pm – asap (weather permitting)

Trophies and medals for 1st, 2nd and 3rd place F1A, B&C as well as medals for 1st, 2nd and 3rd Teams.

Medals for top Junior in each event also! Award ceremony will be presented on Tuesday evening. Champagne will be available for everyone!

(Sunrise for Feb 11th – 6:50 am Sunset – 5:36 pm)

Deviations from the FAI sporting code and special instructions:

Competitors MUST provide their own timekeepers. Two timekeepers per competitor are required for the flyoffs. Fly-off times will be decided on the day depending on the weather.

Team scores will be decided by the total time of the 3 contestants including flyoff times (ie: not as per the sporting code).

Note: A Starting line will be utilized with pole positions (depending on entry numbers).

Please e-mail advance entries to Tony Mathews This email address is being protected from spambots. You need JavaScript enabled to view it. prior to Feb 09th. Entry fees to be paid on the field by Feb 11th (someone will be available to take

entries on the field on Monday Feb 11th from 12:00 pm to 4:00 pm) please do not send money.

LOCAL MOTELS:

Lost Hills Motel 6 +1 661-797-2346

Lost Hills Days Inn +1 661-797-2371

2014 NORTH AMERICAN CUP ENTRY FORM

NAME___________________________________________________________________________

ADDRESS________________________________________________________________________

Country_______________________________________________________Email_________________________________________________________

FAI LICENSE NUMBER____________________________________________________

PLEASE ENTER ME IN:

F1A ($25) ______________________________

F1B ($25) ______________________________

F1C ($25) ______________________________

TOTAL FEE ______________________________

ALL JUNIORS FLY FREE

TEAM EVENTS ARE INCLUDED IN THE ENTRY FEE

SEND ENTRIES TO: Tony Mathews: 2 Tralee Street, Brampton, Ontario, Canada L6Z 2X4 cell: +1(705) 754-5553 E-mail:

This email address is being protected from spambots. You need JavaScript enabled to view it.

Do Not send Money

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