After six years of service, a receiver battery pack in one of my favorite Slope sailplanes failed to hold sufficient charge to power the onboard radio gear. The first symptom was slow servo response, and pack inadequacy was confirmed with a volt-meter check.
It’s generally a headache to remove and replace a battery pack in a foamie because they tend to be buried in foam and glue. In my April 2013 “RC Slope Soaring” column, I described a method for making the receiver and elevator servo accessible in a foam fuselage in case they need to be exchanged or serviced. Here’s a method for making the battery pack more accessible.
Start by digging out the old battery pack, working slowly and carefully, and trying to preserve the wiring. De-solder the old pack, solder the new pack, and press it into place. Add EPP foam to give the new pack a tight fit in the old cavity.
Add nose weight if the new pack is lighter. Charge fully and measure its capacity with a battery tester. Some battery chargers include the capability to measure capacity while discharging a pack. Installing a pack that does not meet or exceed its rated capacity will guarantee a short service life.
When satisfied with the battery pack’s capacity, the added nose weight, and its snug fit in the old cavity, cut an EPP foam plug to fill the slot. Do not glue the battery or the plug into place. They will be secured with filament strapping tape. I prefer to use bidirectional filament tape. 3M Scotch Extreme Shipping Strapping Tape is my favorite.
Before taping the retaining plug into place, mark it boldly so it can be located under the strapping tape with the covering peeled back. Prominently mark the edges of the plug so you’ll know where to cut the tape to release the plug in case your airframe requires another battery replacement.
This method is not as convenient as a hatch secured with magnets, but this is a Slope airplane, and the airframe must be able to take more of a beating than any magnetic hatch.
Slope Soaring Events in 2014
Ten national and regional Slope Soaring events had been announced at the time of this writing in early January. Be sure to check event websites for current information.
1. Cumberland Spring Soar for Fun, March 20-24, Cumberland, Maryland:
Launch by aerotow, Discus-Launch Glider (DLG), high-start or winch, and fly from a mountaintop in big slope lift on the western face of the Appalachian Mountains.
2. The 21st Los Banos Scale Sailplane Event, April 26-27, Los Banos, California:
Entering its third decade of Slope flying and aerotowing of large-scale modern and vintage sailplane models. The steep, grassy slopes of the Los Banos Creek Reservoir provide lift in several wind directions.
3. North Coast Glider Games, May 2-4, Cleveland:
Slope Combat and Slope Pylon Racing on five hills. Altitude Limited Electric Soaring (ALES) and Winch-Launched Soaring if winds are not favorable. There will be indoor flying and a pizza party after dark.
4. Midwest Slope Challenge, May 15-18, Lucas, Kansas:
The 21st running of a venerable Slope flying gathering. It includes a Foam Combat match, a Foam Warbird race, a One Design Race, and an Unlimited class race.
5. 40th Davenport International Slope Race, May 17-18, Davenport, California:
Slope Racing that attracts top pilots from around the world. It has been held in Davenport for more than 30 years, and is now in its fourth decade.
6. Informal SoCal Slope Festival (aka Fake Fest), May 23-25, Cajon Summit, California:
The SoCal PSS Festival, the largest gathering of hardcore Slope fliers on the West Coast, alternates years with Soar Utah. The Fake Fest is similar to the PSS Fest, but without the formalities.
7. Katie Martin Tribute Fly-In IV, June 7, San Diego:
Hosted by the Torrey Pines Gulls at the beautiful Torrey Pines Gliderport slope near San Diego. More information can be found in the RC Groups thread.
8. Alpine Soaring Adventure, June 26-29, Joseph, Oregon:
Events will be held at the Memaloose Airstrip, and a potluck barbecue on Saturday night at the park that adjoins Lake Wallowa. Models can be electric-powered airplanes and gliders, pure gliders, or multirotors.
9. Cape Blanco Slopefest, August 5-8, Port Orford, Oregon:
An informal week-long event, held near the campgrounds of the Cape Blanco State Park. The ridge is flyable in north and south winds, and it supports Dynamic Soaring.
10. Soar Utah 2014, August 28-September 1, Salt Lake City:
Slope pilots from across the country look forward to Soar Utah, (held every other year), especially those interested in Scale models—both sailplane prototypes and power-scale sailplanes. The InterMountain Silent Flyer club focuses on providing a low-key event with an emphasis on flying at several locations during your visit to the Great Salt Lake. An F3F and man-on-man (MOM) race course are available for fun-flying and one official race is typically held on Saturday.
11. 48th Cumberland Fall Soar for Fun, November 6-10, Cumberland, Maryland:
An annual event that has run for 48 years? Someone must be doing something right. Activities include aerotow, big slope lift, and electric-power launching.