Production Update, 23 December 2014

December 23, 2014

Water Performance Testing


ESN-1 undergoes water maneuverability testing at Lake Isabella, California.

Since its completion, ESN-1 has been undergoing extensive flight testing and systems performance verification. The objective of this process is to confirm that the production version of the A5 meets or exceeds the performance of the Proof of Concept (POC), which underwent more than 700 test flights for aerodynamic, hydrodynamic, and systems development. The ultimate goal is to prepare the production A5 for ASTM compliance and delivery to the first customer this spring.

As part of that process, the team performed several days of water testing at ICON’s primary water ops location, Lake Isabella, California. While the POC’s hull design was arguably one of the most modern and sophisticated amphibious hull designs in history, the ICON engineering team pushed ESN-1’s design in an effort to further improve the A5’s water-handling characteristics. With the goal of making the A5 as safe, easy to use, and fun as possible, water testing focused on verifying that the new hull design’s performance exceeds the POC’s in the following areas:

  1. Landing: ESN-1 can land easily at a range of airspeeds and deck angles (attitude) without porpoising (a pitch oscillation exhibited by most seaplanes).
  2. Turning: Aggressive “step-turns” or “carves” on the water can be accomplished, similar to the performance of personal watercraft.
  3. Lateral Stability: Static and dynamic lateral-stability requirements have been met throughout the design envelope in a range of water conditions, gross weights, and center-of-gravity (CG) locations.
  4. Water Handling: The A5’s design limits have been verified in rougher water and larger waves.
  5. Wind Operations: ESN-1 can cope with high-wind situations, especially maintaining water-rudder effectiveness when turning to downwind.
image2 (1)

This full-aft-stick water landing was performed intentionally to test the A5’s performance and confirm that the aircraft does not porpoise in this situation. All tests are performed by professional pilots in controlled conditions. The A5 should always be flown within the operating limits defined in the Pilot Operating Handbook.

To test these parameters, ESN-1 was subjected to the full range of weight loadings and CG positions. In the photo below, CEO Kirk Hawkins is evaluating the A5’s upper porpoise limit by performing a full-aft-stick water landing at minimum speed. The purpose of this exercise is to intentionally land the aircraft tail-first to determine if it will porpoise, a task that involves a highly unusual landing attitude that appears visually unsettling but enables the ICON team to evaluate the A5’s capabilities.

While testing at the lake, another amphibious aircraft, a Grumman HU-16B Albatross, dropped in for some practice landings. The Albatross was produced from 1949 to 1961 and saw service in a number of military and Coast Guard roles including combat and rescue service in both Korea and Vietnam. This plane, S/N 51-0019, was built in 1951 and spent time in both the U.S. Air Force and the Philippines Coast Guard. The plane’s purchaser landed at Lake Isabella en route to its new home in Texas. With twin 1,425 hp Wright Cyclone radial engines, a gross weight of over 30,000 lbs., and a wingspan of 96 ft. 8 in., the Albatross is a truly impressive aircraft.


The A5 POC flies alongside the Grumman HU-16 Albatross.

Flight Training Update


Lead Aero Engineer and Test Pilot Jon Karkow (left), Director of Flight Training Jeremy “Hilda” Brunn (center), and CEO Kirk Hawkins (right) discuss how the A5 will be used for flight training.

The activities at Lake Isabella also helped the ICON Flight Training (IFT) team further refine the flight training program, which will deliver comprehensive curricula for both novices and pilots with different skill levels.

ICON’s training program is being as carefully designed as the aircraft itself. Under the leadership of Director of Flight Training Jeremy “Hilda” Brunn, program development is underway which is centered on teaching relevant competencies with an engaging and dynamic curriculum. It is tailored to instill the knowledge, discipline, and aviation skills necessary to operate the A5 confidently and safely.

The ICON training experience will encompass full-scale simulator work, ground training, water operations, and flight training focused on visual-contact flying techniques. In addition to essential stick, rudder, and throttle mechanics, the program will instill disciplined habits and decision-making strategies specifically tailored for amphibious operations. The measure of success for IFT will be achievement of true competency in the fundamentals of reliably and safely operating an aircraft in three dimensions, at low altitudes, both on- and off-airport, on land or on water—while simultaneously having the time of one’s life. By equipping participants with a world-class training program, ICON intends to make A5 owners the best and safest pilots possible.

ESN-2/ASN-1 Production News


ICON technicians install flight-control components into the ESN-2 fuselage, which will be used for structural testing.

The ICON team has completed structural assembly of the Engineering Serial Number 2 (ESN-2) fuselage at the Tehachapi, California, production facility. The structure has been fully instrumented with strain gauges and will undergo testing to ensure it complies with ASTM strength requirements.

ICON engineers and technicians are simultaneously assembling Aircraft Serial Number 1 (ASN-1), the third production A5. ASN-1 marks a significant milestone as it is the first aircraft that will be delivered to a customer, culminating years of research, development, and design leading to serial production. ASN-1 will undergo FAA inspection to ensure the A5 complies with ASTM standards. In addition to the aircraft itself, FAA representatives will review ICON’s manufacturing facility and documentation/quality systems before serial production proceeds.

Related Updates