Wednesday, September 7, 2011

Aluminum Plane: Real Flight Data Graph

One of the joys of this project is the performance of the product:  the aluminum plane rocks.

Here is a "GPS Essentials" flight data chart from a recent flight in Aluminum Plane #1:

Belite Ultralight Aircraft Performance Graph
I marked two locations with yellow dots.  The difference between these dots in time is about 3 minutes, and the altitude gain is (2070-1500) = 570 feet.  This is a calculated climb rate of 225 feet per minute.  With a forward airspeed of about 43 mph in the climb, the actual climb angle was about 5 degrees, and the deck angle was probably around 12 degrees.  Climb rate was NOT maximum.  (although it was probably close).  I weigh 200 pounds, plus some gas on board of course, and density altitude was about 3300 feet at ground elevation.

All this with a tiny 28hp engine.

You can also see some two pass runs, demonstrating cruise speed.  With the wind, ground speed averaged about 64mph and into the wind, ground speed was 47mph.  The average is 55.5 mph, once again, with a 28hp Hirth F33 engine.

Fun, fun, fun!

- James

Tuesday, September 6, 2011

"This Belite Be No More"

And this is a very sad story, with one fantastic testimony to the crash worthiness of our airplane.

The 80+ year old pilot was observed to take off in the Belite Superlite, barely gaining enough altitude to clear a fence.  Apparently, the pilot did not command the airplane to turn in any direction, climb, or descend back to the ground, which was just a few feet below him.  Nor did he retard the throttle, which was reported at 'full' by an observer.  (The Superlite is capable of climbing out at fairly steep angles.)

After continuing in this manner for a handful of seconds, he crashed into the side of a distant steel building, still under full power, still just a few feet above the ground.  I have not seen the accident in person, but I do have one photograph.  It seems to show a very hard impact of the left wing tip, then impact of the main structure of the fuselage.  The wing ribs and spars are carbon fiber, and the fuselage is chromaloy steel -- all very tough stuff.

The pilot was wearing his seat belt / shoulder harness, and escaped the accident with broken ribs.  The cabin structure of the Belite, along with the safety harness, probably saved his life.

The metal gas can did not rupture.  (It is optional equipment.)  The parachute did deploy at impact (probably due to stretching of the release cable in the accident.)

We are very saddened by this accident and wish the pilot a speedy and full recovery.

Belite Ultralight Aircraft Accident

More Info: Ultralight Aircraft Aluminum Fuselage

The #2 Aluminum rear fuselage is taking shape nicely.  This particular aircraft is destined to be a tricycle gear airplane.

Everything you see here is weighing in at about 33 pounds, including tricycle mods.  I am pleased.  We had taken a 'weight bump' but have gotten some of the weight back out by trimming excess off cross members.

We're waiting to mate this fuselage with carbon fiber spar wings; we're currently out of stock on the carbon fiber and waiting for a shipment to come in.  As a result, the fuselage will not be flying until around Thanksgiving.  It is scheduled to deliver to a customer in December.

Please note the gas tank / cargo compartment.  It's designed to hold a 5 gallon plastic tank, for easy swapping.

The purpose of the side aluminum sheet panels is to spread landing gear loads from the gear into the fuselage.

It would be very easy to 'metalize' this entire airplane.  I hope some customer chooses to do that.

Belite's Ultralight Aircraft Aluminum Fuselage

Close up of gas compartment.  Optional lid over this, along with panels to close off the compartment.

Detail of tail section.

Tail Section, another view.

Belite's Aluminum Ultralight Aircraft fuselage