When we first began working with our engineers, we broke down our design specifications into two major groups: Requirements and Goals.

Simply put, requirements were items that had to be included or specs that had to be met.  Conversely, goals were things that we felt would be nice to have, or things that were "cool" but could be costly or heavy.

Below are the edited and annotated program requirements and goals, with a little commentary at the end.
Requirements:

  • Aircraft is safe in all flight regimes
  • So far, so good.  Flight testing to date has not revealed any bad habits or unsatisfactory flight characteristics.

  • 2 seats, in tandem, with rear occupant elevated for good visibility
  • Done.  The rear occupant (spouse, father, mother, brother, sister, best buddy or student) is elevated above the front seater by about 8.5 inches (22 cm).  It is a really good view.

  • Twin boom pusher configuration
  • Done.  It isn't the easiest configuration in the world to engineer and build, but it does allow for that great pusher visibility and it looks very sexy (and you'll look sexy flying it, won't you?)

  • Interchangeable wing sets for cross-country flight versus slow sightseeing flight
  • Done.  You can buy one or both sets of wings, depending on your personal desires.  The cruise wings give you some extra knots of cross country speed, but their stall speed will be above the LSA limit--if that's important to you, stick with the slow wings.

  • Minimum of 20 gallons of fuel (safe stowage)
  • Done.  Fuel tanks are in the wing roots and the current  capacity is 24 gallons.

  • Capable of safe flight with engines within an 80-125 HP range
  • We have dropped all pretense of flying this thing on anything under 100 HP.  Once you see it in person, the plane is physically pretty large.  Two big people on a hot day with full fuel on 80 HP is a bad idea.  We want to see you have at least 100 HP to stay out of the trees.

  • Provision for mounting a ballistic recovery chute
  • Done.  It can be mounted to the front of the firewall, behind the rear occupant.

  • Provision for cockpit heat
  • Done.  Not a big deal.

Goals:

  • Take off roll of approximately 500 feet or less
  • It's closer to 750 depending on the day.  This only holds true for hard surface runways . . . grass has a higher rolling friction.

  • Wings should be attachable / removable without tools by one person in 10 minutes or less
  • Done, although you do need a socket.  We copied a common pin-and-fork mechanism that has been around on sailplanes for decades.  Although you CAN do it by yourself, you SHOULDN'T.  Why not?  Because sooner or later you will drop one of your wings.  They don't weigh much, but they are fairly big and awkward.

  • Climb rate of 1,250 FPM or greater with 100 HP engine
  • We have climbed the prototype as hard as 1,700 FPM.  Weight and prop pitch are, of course, the two biggest variables.  In a high/hot/humid/heavy condition it is reasonable to assume a climb only slightly in excess of 1,000 FPM whereas a cold/dry day with a climb pitched prop will climb like crazy.

Design Goals
The contents of this web site are wholly owned by Vulcan AeroForge LLC, d/b/a Ion Aircraft.
"Ion Aircraft" is a registered trademark.
Copyright, Vulcan AeroForge LLC.
All rights reserved.  We mean it.