History of Le FishEdit
The Le Fish design drawing was completed by Steve "Surfimp" Lange on November 19th, 2005, and was first shown in public on the RCGroups.com Slope forum on December 26th, 2005. After a build documented in a RCGroups build thread, the first prototype flew on April 13th, 2006 at Grant Park (aka "The Cross") in Ventura, California.
Based on the positive results of the maiden and subsequent flights, and immediate demand for the design from other forum participants, Le Fish went into production with Leading Edge Gliders and was made available for sale on April 25th, 2006, where it has remained one of the company's best selling designs ever since.
On April 6th, 2012, a CAD plan based directly off the original design drawing was released as a downloadable PDF from SlopeAerobatics.com. The CAD plan was released under a Creative Commons Attribution-ShareAlike 3.0 license, following Steve's firm commitment to an Open Source philosophy regarding glider design.
In the early 2000s, there were relatively few fully aerobatic R/C gliders available in the global marketplace, and none domestically produced in the United States. The gliders that were available were primarily French designs (or derived from French designs) and all of them featured fiberglass composite construction. Readily available examples included the Aeromod Voltij, Airtech-RC Jedi, Sonic and Psycho, and the Topmodel Kulbutin (which itself was based loosely on the Madslide design of Benoit Paysant-Le Roux).
There were also a variety of scale models of fullscale aerobatics gliders like the MDM-1 Fox, Swift S-1 and Pilatus B-4, but in virtually all cases, these scale models used semi-symmetrical airfoils that limited their inverted performance to some degree.
All of these gliders - whether scale or non-scale - tended to require moderate (12-15mph / 20-25kph+) or better wind conditions to really come alive on the slope, and with few exceptions (eg. the Kulbutin), they were optimized for precision aerobatics, also known variously as "classical", "academic" and/or "pattern" aerobatics. Generally speaking, these gliders performed their best aerobatics either in "big sky" conditions featuring abundant lift and generous amounts of airspace, or over flatland (via aerotow, winch or bungee launch) performing a traditional descending glider aerobatics routine.
VTPR and the MiniToonsEdit
In May 2005, Pierre Rondel of Planet-Soaring.com participated in a thread on RCGroups about the open source MiniToons EPP aerobatics glider, a then-new design by Jérome Bobin of France that first flew in the spring of 2004. In so doing, Pierre also introduced the wider English-speaking audience to the French phrase Voltige Très Près du Relief, or VTPR for short, which when translated means "aerobatics very close to the ground."
The VTPR flying style was synonymous with the slopes of Brittany in the northwest of the country, and by 2004 it had become quite well-known throughout France thanks to publication of glider plans and essays in various French modelling magazines such as Looping. VTPR was notably distinct from "classical" precision aerobatics in that the figures were flown extremely close to the ground - usually at about eye level, give or take - and the gliders themselves were extremely lightweight for their size. A 2.5m VTPR aerobat like the Excalibur tipped the scales around 52-60oz / 1500-1700g - about the same as physically much smaller 2m precision aerobat. These low wingloadings served to slow the planes down somewhat, reduce the stall speed, increase their agility and lessen the kinetic forces when the inevitable impacts and crashes occurred: all attributes designed to make them superior to other designs when flown very close to the ground.
The MiniToons was intended as a low-cost, easy-to-build glider meant specifically to help more pilots get started flying VTPR via a fun, durable EPP design with enjoyable performance. The MiniToons's CNC cutting files and PDF build instructions were released as open source, free downloads on the EPPConcept website run by Laurent Lombardo, with the hopes that making the plan available in this way would help spur broader interest in VTPR aerobatics.
Upon seeing a video of Pierre Rondel flying the MiniToons at a coastal site in Brittany, Steve Lange immediately recognized VTPR as identical in spirit to a style practiced in Santa Barbara referred to as "In Your Face" flying. This style was mainly flown with small, manuverable and very lightweight EPP gliders such as the Dream-Flight Weasel and was characterised by highly aerobatic figures performed extremely close to the ground and the pilot(s), often exploiting small gullies and bowls in the face of the slope as well as making ample use of "weed whackers" - touching the belly, wingtip or vertical fin of the glider against grasses or small bushes while passing by.
Steve was already actively practicing precision aerobatics with an Aeromod Voltij, but the interaction with Pierre and the MiniToons concept sparked a quest to acquire an aerobatics glider that was both durable and capable of flying in light lift - in essence, "a Weasel with a rudder and perfect inverted flight." If he were able to own such a plane in addition to his Voltij, Steve felt he would then be able to fly aerobatics in all typical conditions in the Santa Barbara area - "all acro, all the time."
Scratching An Itch: Birth of Le FishEdit
After trying unsuccessfully for about six months to find someone in the U.S. who could cut him a MiniToons using the CNC files from EPPConcept, and put off by the high cost of shipping the EPP parts from France, Steve decided to design and build his own glider instead. He approached Jack Cooper of Leading Edge Gliders with the idea, and Jack, who had helped supply parts for a number of Steve's previous scratchbuild projects, happily agreed.
Steve drew the Le Fish design freehand on graph paper in small notebook, erasing and re-drawing it until it looked "right" to his eyes. Having previously decided on a wingspan (60" / 1.5m), he measured that dimension with a ruler and then determined the rest of the dimensions accordingly. He sent these off to Jack along with a scan of the drawing to serve as the basis for the prototype, which Jack cut using a hotwire cutter for the wings and a bandsaw for the fuselage.
The resulting Le Fish design was based loosely on the MiniToons concept, but differed in a few significant ways:
- Inspired by Steve's experience with the Dream-Flight Alula, the North County Flying Machines Moth, as well as a scale model of the MDM-1 Fox, the wing had a straight leading edge, giving it a slightly forward swept quarter chord (as compared to the unswept straight tapered wing on the MiniToons);
- The fuselage was to have a tapered symmetrical airfoil shape from nose to tail when viewed from above (as compared to the flat plate profile of the MiniToons fuselage);
- The design was intended to utilize then-prevalent American EPP building techniques including wooden aileron and tail surfaces (rather than the Coroplast on the MiniToons), as well as strapping tape, iron-on covering, and thinned Goop reinforcements (versus the packing tape finish of the MiniToons).
As with the MiniToons, Le Fish used the proven SB96V (root) and SB96VS (tip) airfoil combination, which had been used to great success on a wide number of French designs and to this day remains one of the reference airfoil combinations for VTPR gliders. A note of trivia: the original Le Fish plan shows the MG-05 airfoil - the same one used by the Voltij, a plane Steve was flying a great deal at the time - but in the end the SB96V/VS was selected instead.
Further inspiration came in the form of the control setup adopted for Le Fish, which was based on what Steve had learned from flying the Voltij. This setup used always-on snapflap mixing for its fullspan flaperons as well as a 4 Axis -style sprung throttle stick to provide dynamic camber and reflex control. A final influence from the Voltij was the angular shape of the false canopy adopted in the finishing scheme, which Steve intended as an conscious homage to the Aeromod design that had inspired him so much in the pursuit of slope aerobatics.
Le Fish Makes a SplashEdit
The first flight of Le Fish occurred on April 13th, 2006 at Grant Park in Ventura, California. Three days later, the first Le Fish video was released, showing the plane flying in moderate 10-12mph lift at Farren Road in Goleta, California:
Public response to the video was immediate, and Jack Cooper of Leading Edge Gliders put the design into production on April 24th, 2006. To date, thousands of Le Fish have been sold worldwide, and Jack has indicated it has been one of his perennial best-sellers.
Swiss Peter and the Ultralight RevolutionEdit
While EPP construction and laminating film covering are both well known in the slope soaring world, they had previously mainly been used in heavy-duty applications for combat wings and dynamic soaring. The way they’ve been combined in these ultralight aerobats is novel, and was pioneered in 2011 here in Santa Barbara by Peter Richner, also known as "Swiss Peter."
Peter has been heavily involved in R/C flying since he was a child in Switzerland and has tremendous passion and motivation to bring innovation to the hobby. Drawing on his experience flying powered 3D planes and deeply inspired by the Dream-Flight Alula, Peter tried to see if he could unlock new possibilities for slope aerobatics by pursuing an ultralight wingloading. Using my Le Fish and Spindrift designs as a basis for his work, he built a series of prototypes to successively lower and lower weights, ultimately producing a Spindrift with a ready to fly weight of only 13.7oz (390g) - completely unheard of for a 1.5m (60”) EPP aerobatics glider!
It was thanks to Peter’s innovation that I was finally able to realize my original vision for the Le Fish... a fully aerobatic glider that could fly in the same type of light lift as a Dream-Flight Weasel and able to take the same kind of abuse. However, the flying weight of original Le Fish prototype, built following traditional methods derived from combat wings and Power Slope Scale ships, was 38oz (1080g) with a wingloading around 10oz/sq.ft (30g/dm2). While this produced a fun, durable and capable glider, it isn’t able to fly in very light lift, requiring around 10-12mph to really come alive. Following Peter’s techniques, we are now able to build a Le Fish to a sub 21oz (600g) flying weight with a wingloading around 5oz/sq.ft. (15g/dm2), and can discover, as Peter had, that an entirely new world of aerobatic performance is unlocked.