Allard van Wallene: flaps

Exspan 2004

This is Allard's original ExSpan design. Development started in 2003 and it had its first public outing at the 2004 Holiday on Ice.
This version uses a conventional tow hook and ABAS timer.

Systems Outer flap drive

The systems: the flap drive servo is on the left with the stabiliser servo immediately behind the hook.

Outer flap drive.

Section, flap up Centre section

The wing section with the flap raised to demonstrate its position during ballistic cruise.

Centre section showing wing attachment.

These photos were taken at Holiday On Ice 2004 by Mike Woodhouse of Free Flight Supplies.

The flap is under proportional servo control. It is set to glide position during tow, lifted slightly for acceleration and pitch up and moved full up during up ballistic cruise and bunt. It is then lowered for fast glide and glide before being pushed full up again for faster d/t.

This was the first flapped F1A to withstand all out bunt launches. Here is Allards development timeline:

ExSpan 2004 plan

Click the plan for a higher resolution image.

Exspan 2006

The 2006 version is fitted with a Flexhook tow hook and ABAS timer.

ExSpan 2006

ExSpan 2006 plan

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