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At the Last Meeting... [Content thanks to Paul Jackson]

The scheduled SAM general meeting on September 6th was postponed until the 13th due to the holiday weekend. The meeting on the 13th was attended by 19 members and one guest. The financial report was read by Carlos Rangel; currently we have $1200.44 in our balance. The increase over August, which was $643.81, was due to new members' initiation fees and payments made by members on the field assessment.

A discussion of the Bylaws changes was held and voting on these changes will take place at the October 4th general meeting at the field. Please plan to be there!

Our Night Fly event coordinator, Howard Brown, has been unable to secure a Saturday night date for our Night Fly due to ongoing race track activities. Such efforts will continue however. We should hopefully allocate a dark night suitable for this event before the end of the year.

President Marv Kea noted that we need to put a concrete pad under our Port-a-Potty and securely fasten it to the ground to minimize additional wind damage. Estimated cost of the materials will be between $100-150. A work party will be held in October (date to be announced) to help spruce up the field.



From the Puckerbrush... (Editor's Column)

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Tip of the Month: Canopies make lousy landing gear. Just so you know. :)

Top 10 uses for an Ugly Stick: [Courtesy of the Flying Penguin of S. Florida; Robert Osorio, Editor. Apologies in advance to Stick fliers... ]

Coffee Table Paper Weight
Doorstop Weed-wacker
Personal Defense Device Fireplace Fuel
Chew-toy for Large Dog Step Stool
Hammer Wheel-chock for 1/2-scale Piper Cub

The following are acronyms used in popular R/C computer radios nowadays. All too often, the manuals (translated from Japanese to Sanscrit to Swahili to Russian and then to English, or something like that) never tell you what the acronyms actually mean! Robert Osorio reports here, for the first time, a listing of the actual meanings of these acronyms:

PPM - Please Press Me PCM - Please Crash Me
FLPR - Flaps Loose, Prepare for Release RFL - Rudder Flapping Loose
RGOG - Retract Gear On Ground EPBBC - Eject Pilot Bust Before Crash
TMGR - This Makes it Go Right TFMS - Try and Fly Me Stupid
SYTS - So You Think So? EAM - Erase All Memory
DTOB - Don't Take Out the Battery WGDM - Wait a G#d D##n Minute!
TBMC - This Button Makes it Crash TLS - Turn Left Stupid
GRQM - Get off Runway Quick Mode MBC - Make a Big Crater
TRTR - Turn Right! Turn Right! FBBF - Fry Buddy Box Function
SDE - Shoot Down Everybody TMFE - Too Much Frigging Elevator


Mail Call by Paul Jackson, Secretary

Weekday Fliers Wanted!

For those new pilots in the SAM club, I am at the field most Tuesday and Thursday mornings. If you need help on the buddy cord, come out and join us.

Bylaws Reminder

7.7 PIT AREA

-Paul


Calendar of Events


SAM Swap Shop To have your ad placed here, contact your friendly neighborhood newsletter editor today!


Club Instructors are:

Keith (Bear) Brock, 721-7170 Marv Kea, 722-4569 Craig Kulesa, 318-9510 Paul Jackson, 296-9726
Carlos Rangel, 296-0622 Jerry Ratzlaff, 749-3830 Ben Reynolds, 790-6873 Chris Tanner, 647-7238


Float Flyin' Fun (Part 2.718281828)

This article is a continuation from July's Newsletter, where we discussed the construction of R/C floats; and August's Newsletter, where we briefly answered questions concerning aircraft behavior on the water. This month we conclude our water flying series with miscellaneous issues we have not yet covered in previous months.

Float Shape

One issue we have totally ignored so far is the shape of the float. From the side, most floats have a similar cross-section. From the July 1998 Newsletter, I made this diagram of a float's pertinent features:

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This is only part of the story, however. There are dozens of designs for how a float should look if viewed from the front (i.e. the cross section that'd result if you snapped a float in half - not that I'd ever recommend that of course). Two of the simplest and most common float designs are the ``flat bottom'' and ``V bottom'' floats, as shown below:

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Other designs add cambered curvature to the bottom of the float, much like the hull of a boat:

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Proponents of each type of float will argue vigorously about the capabilities of each type of float. The ``V'' design is reputed to cut through the water and send the spray outwards. The curved ``cruiser'' bottom adds angular momentum to the spray as it is sent out, adding lift to the float. ``Tunnel'' floats attempt to trap the spray, aiding in hydroplaning. On the other hand, the most popular and arguably the most successful design for R/C planes is the plain flat-bottom float. Namely, a flat-bottom float:

Full-scale planes, however, rarely use flat-bottom floats because of the high wing loadings encountered; flat-bottom floats would simply get bashed up due to the pounding of water at high speeds. This led directly to the development of ``V''-type floats, which serve to deflect the water as well as displace it. This tends to move the spray upwards and into the prop arc. More complicated float designs, with many curved segments (the simplest of which are the ``cruiser'' and ``tunnel'' designs above), are designed to control the direction of the spray.

So for small R/C planes, flat bottom flats make an optimal choice (although others work well too). For the largest R/C planes, one might begin to consider alternatives seriously. More important, however, is the actual construction of the floats (see July's Newsletter). Especially crucial is ensuring that the chines and steps are sharp. The chine is the edge between the bottom and sides of the float. The step is the discontinuity on the bottom of the float, about halfway back. Keeping these edges sharp will ensure that water moving past will leave the float cleanly and allow the float to break surface tension with the water. Happy splash 'n goes!!


Until Next Month...

Give me your Swap Shop advertisements, comments, article submissions; support your local hobby shops, avoid CA-ing your fingers together, and stay out of the puckerbrush. Happy quiet landings, everyone...

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Back to the Newsletter Index


Craig Kulesa
Fri Dec 4 21:26:26 MST 1998