SEFLI X-SOUNDER Project

In the early morning of July 7th, aviation history was again made on Long Island.

The Silent Electric Flyers of Long Island took up the task some 6 months ago of designing, building, and test flying a vehicle capable of making the journey. Approximately 15 members were directly involved.

A full all-telling article will be presented in MAN later this year.

Just as a teaser though....some basic facts:

• 100" wingspan
• 1500 sqin wing area
• 7 lbs RTF
• Aveox 1415-4y motor (direct drive)
• Schulze 55bo sensorless controller
• APC Electric 14 x 7 prop cut down to 12.5"
• 14 Panasonic 3000 NiMH cells
• Super Circuits PC87 miniature video camera and Tx
• 4x1000 mAh NiHM Rx pack
• 8x600 mAh NiMH for video power

• Take off motor current: 24amps
• In-flight cruise current/voltage: 3.5A/15.5v (measured by a home made down-link watt-meter)
• Cruise speed: approx 20 mph
• Flight time: approx 45 minutes.

(Note: There were NO NiCDs anywhere on board! (Even the TX had and 8-cell 1600 NiMH pack!)

Bob Erbe (15 ft Boston Whaler boat captain), Mario DiDiego (communications officer, ship-to-shore radio and video) and myself, Tom Hunt (seaplane pilot) rose at 3am to fight off the fisherman at the boat ramp in Port Jeff to get a good spot. Clyde Geist (VP of SEFLI) and Henry Prew (Pres of SEFLI) were high above the sound in Clyde's Cessna 172 taking air-to-sea pictures.

The model took off just inside the Port Jeff jetty into a slight headwind (approx 4 mph) and 45 minutes later landed less than 1/2 mile from the CT shore in 3 ft of water. The headwind (20% of flight speed) was too much to overcome.

Undaunted, the cross-sound crew swapped out the motor battery for a fresh pack. The model took off towards the CT coast (approx 200 yards away), crossed the shore and turned SE back towards Port Jeff, Long Island. Now, with a 4 mph tailwind, not only did the model cross to the LI shore easily, but the model was then flown into the harbor, past an exiting destroyer tender and x-sound ferry, quietly snuck up to the docks at the far south end of the harbor and made 2 victory laps before it landed less than 50 yards from the boat ramp. The total distance traveled shown on the GPS was 15.7 miles.

Digital still photography was taken from the chase boat, as well as sporadic 8mm video. Video from the camera onboard the model was recorded on the chase boat also.

Now.... if you thought this was easy.... think about it....:

get a 7 lb seaplane off the water.... cruise on less than 60 watts (the painful output of one Sp400 motor!) continuously for 45 minutes and do it at 20mph (not terribly fast even for a model!) Do it without gliding, or thermal assist!

Next? a round trip? feasible? yes, but it may take a new model .... but most of all?