My
apologies for those following this blog. I really did not
intend to take such a long break from the project but summer got in
the way and after my fiasco with the covering process I was having a
hard time getting back into it. A significant part of this
project involves finishing the completely enclosed trailer shown in
the very first post. I completely removed the shelf system and relocated them to a position about 4" lower that made use of all the wasted headroom over the lower wing set left by the rib camber I had not taken into consideration originally. There was also a considerable amount of epoxy/ fiberglass repair that needed to be done and a
reconstruction/re-design of the end panels to accomplish a
weather-resistant seal on both ends. I also removed one of two
leafs in the suspension system (the photo is after I removed the small leaf) and added shocks on both sides to
smooth out the ride.The
shock/springs came off a Harley Sportster mod job....still need to
see if they are too stiff.
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Currently
I'm working on the bed that I will need to attach the box to and then
I'll try out the suspension system with a full load.
Mid
July I had an opportunity to inspect the covering of an Icarus II
that was done by someone I knew to be a “craftsman”. I figured
this would give me an idea what was possible in doing a good job of
covering this type of airframe. Here are a couple of shots showing
the leading edge area and the rib sag.
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My
conclusion after looking at this was that it is possible to get a
very nice, wrinkle-free covering with very little inter-rib sag.
Keep in mind that nitrate dope keeps on shrinking years after it is
applied so the rib sag you see in this picture must have been near
zero when the glider was covered.
In
July, I flew Fort Funston and happened to meet a former Easy
pilot who ended up giving me his Easy along with the car top box he
built to transport it. He flew it one last time in what I guessed to
be winds at the Fort over 20. He is taller than I am, maybe 6' and
probably has about 25-30 pounds over me and he had all he could do to
maintain control on the ground with the glider. I learned a lot by
watching him fly it. He used no rudder control on the ground (said
it really wasn't effective). He told me that pitch control is really
all you have plus body torque to get and keep the wings level while
ground handling. Once in the air flow he had a lot of pressure on
each hand placed forward on the twist grips to keep the nose down. He
could pull down a high wing by pushing down harder on the high side
but I never saw him do anything with the rudders. I had to come in
twice at his request before he launched to pull down a wing that he
could not pull down on his own. Once in the air it looked really sweet.....easy,
comfortable flying position and an effortless landing. He did tell
me to start flying it before I put too much more time into my project
to make sure I am happy with it's performance. He said the sink rate
wasn't all that good. I expect I will do significantly better than
he did since I am quite a bit smaller that he is. He had it rigged
with a compressed air chute deployment system that a friend of his
was making at the time and he used it on that last flight. I will
need to rig my own system once I start flying it at high altitude
sites. Here's a shot of me on the way home from the Fort with Darrel
Robbins' Easy in it's car top case and my Comet on top.
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Here
are a couple video links to Darrel's final flight in it the day I
returned to Oregon.
Keep
in mind that the wind at launch was gusting over 20.
The
glider itself has some tears in the sail that I will repair before
taking it out. Here it is shown in it's new home (the box I built
with the reconfigured shelf mod I did in June).
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Had
over an hour talk with Brian Porter last night on the phone where we
discussed various topics including things to pay attention to in
building the glider and also tips on what he found worked for him in
flying it. Brian was one of the experts at flying rigid wing hang
gliders back in the day. He won the Escape Country meet with the
Easy Riser in 1976. He mentioned increasing the washout to a 2 5/8
inch block on the fabrication frame vs 2 ½ specified in the plans.
This was thought to improve the sink rate. I asked him about
covering and his comments indicated that he was able to pull a lot of
spanwise tension in the cloth without dog legging the frame. No tips
on how he was able to do this. It could be the fact that I tweaked
the frame when I crashed is setting mine up to dog leg with even
moderated spanwise tension. I am beginning to believe this is the
case. If true, then my only solution is to go light on both spanwise
tension and chordwise tension living with a few wrinkles or bend the
frame back to straight again. He said the glider is prone to pitch
sensitivity and will pop up and down in thermals.You get used to it
after a while. If properly built, the glider should trim out so that
once in the cage, feet on the leading edge, you should not be able to
stall the wing even with your back up against the rear of the cage
but this should put you at minimum sink right above a stall. You
have to let your feet down to get it to stall. You can see him drop
just one leg and then bring it up again as he adjusts his approach
for the spot landing in the video link I'm including below. He also
fabricated handles that he mounted 90 degrees off the twist grips to
aid in rudder deployment. He said you'd be surprised at how
tiring it is to work the twist grips for an hour. The front negative
wires were replaced with 3/32 cable since they will see a large load
if the wing goes negative. The plans called for 1/16. He recounted
inspecting a wreckage where these cables broke when a fabric
detachment occurred and caused an involuntary tuck. Deploying both
rudders will pitch the nose up since they are above the center of
mass in the loaded air frame. This video link to YouTube shows
footage of Brian doing an approach where you can see how he moves his
legs and how the glider responds as he flies into ground effect and
flares.
The
current state of the project is both upper wing panels are ready to
cover. I have the pre-shrunk material and am winding down my
summertime activities. I hope to begin covering again in September.
My first priority is to finish the trailer so I can move the wings
when I finish them. Without the trailer being ready, I have no way to move the wing panels to and from the shop which is about 8 miles from my house (I have no wing frame at this shop). I am also anxious to repair the fabric on Darrel's glider so I
can begin to take it to the beach and learn how to fly it before
winter sets in.....decisions, decisions.
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