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Archive for November, 2006 - Page 2
Posted by Jack Crossfire | Nov 07, 2006 @ 04:33 AM | 5,219 Views
That's right, battery freaks, Max Amp arrived. 4000mAh, 11.1V. Until today, the Hyperion was considered the best of the best. Now Max Amp is the best of the best.

11/6/06 flights:
Max Amp 4000mAh
35min

Hyperion 3300mAh
27min
Magorator seemed considerably dimmer, which prevented flying far away.

For a total of 62 minutes off the ground, 20 minutes longer than the Blue Angels can fly. Can't believe how inferior the Hyperion now feels,
but that's technology evolving. A couple years ago it was nihilistic to fly just 8 minutes at a time.

Now there are kids who load down their copters with beepers, buzzers, fancy lights, and soft cutoff speed controllers to warn them of low
battery voltage. We've had success just timing the flights. When the throttle starts softening, look at the time during a stable hover. When
the throttle is still softening and the time is around maximum, fly 2 your flight box and hover just above the ground until motor shutoff.

11/4/06 flights

1 video flight + 2 night flights
Strong wind prevented long nose-in hovers on 3rd flight.
Nose-in landings & takeoffs started on 2nd flightn

Entered the nose-in takeoff & landing world 4 the first time on flight #2. So far it's mainly nose-in takeoffs & nose-in controlled crashes.
Can hold a nose-in hover without any wind for as long as we can stand it. Definitely not as fun as nose-out hover.

On flight #3 got the first night flying photos.


Incidentally, discovered Max Amp by reloading rcgroups.com over and over and clicking through banners ads. Proof again that banner ads work.

Max Amps bounced back to 10V after motor shutoff. Hyperion still bounces back to 9.5.
Posted by Jack Crossfire | Nov 06, 2006 @ 03:51 AM | 5,721 Views
Although the footage wasn't nearly stable enough to justify it, ran a stabilization pass on it. Since most people don't have the computing power 2 play HD, we're not offering the high definition copy, but the high definition quality is better than anything achieved before on a consumer platform, simply nihilistic.

Software stabilization gives you an idea of what it would look like if the camera pitch and yaw were somehow decoupled from the copter. The uncontrolled roll doesn't take away as much as you would think. A proper gyrocam is way too heavy.

Low definition copy:
http://kpax.pioneer-pra.com/~heroine...crop_small.mov
Posted by Jack Crossfire | Nov 05, 2006 @ 08:53 PM | 5,384 Views
Today's location was southern Laytanton for the absolute lowest wind of the valley. 20mph. It's so consistently windy in Calif*, 1.5% of the universe's power comes from wind.


Enclosed skids completely in foam and that combined with lower rotor speed greatly reduced vibration. Since the radio antenna was attached to a skid, it was also enclosed in foam.

Enclosing of the radio antenna caused rapid loss of reception at long distances.


The higher blade pitch is undeniably much quieter. It's better than the Comanche.

In high wind and with the low rotor speed, tail rotor was completely ineffective. The tail rotor is driven by the main rotor, you see. After fighting for some time to achieve left rudder at high altitude, lost tail rotor completely and entered flat spin. Added cyclic to control the descent but that proved disastrous. Sideways crash into U. Know. What. S.A.

Next time, don't touch the cyclic and just use the throttle to try to put it down away from the property. The loss of tail rotor was due to our 3/4" tail boom padding getting pushed into the tail rotor by aggressive rudder movements. Need to secure that.

After burying the camera mount, it was time for the second crash. Seems this location in southern Laytanton has strong downdrafts from the surrounding hills. Entered a downdraft while flying downwind, descending, and that caused vortex ring state. The reflex action is of course to add forward cyclic, but with the wind from...Continue Reading
Posted by Jack Crossfire | Nov 05, 2006 @ 04:16 AM | 5,279 Views
Squeezed in one battery charge in clear weather, using the 5&deg blade pitch, still increasing nose-in durations.

For the final battery charge, increased blade pitch to 6&deg. Much quieter flying than 5&deg but it may have been the fog. Final battery charge was flown in the worst fog so far. The problem was equally seeing the copter and seeing the ground. Forget about flying more than 30' away and forget about flying fixed wings in this fog. That's why they make copters.

Observed water dripping from the tail boom but it flew nominally. 6&deg pitch offered the same flying time as 5&deg but quieter.
Posted by Jack Crossfire | Nov 05, 2006 @ 12:43 AM | 5,512 Views
Finally good enough at flying to mount some cameras. The camera mount is real heavy.

Kept spooling in throttle without getting anywhere until it finally took off around full power. Vibration was unbelievable due to the rotor speed hitting a resonant frequency. Autofocus was completely non-functional. In the air, the camera mount ended up supported by the string instead of the 3/4" padding, which caused too much vibration.

There is no footage worth downloading from this run....Continue Reading
Posted by Jack Crossfire | Nov 04, 2006 @ 05:12 AM | 5,495 Views
11/03/06
27min
5mph wind, 60`
250mA

27min
10mph wind, 15mph gusts, fog, 60`
2A

27min
10mph wind, 15mph gusts, drizzle, 60`
2A

Getting 3 flights in between a 2A charger and the sprinkler schedule is pretty tough.

Can say this lithium battery isn't fading the way other lithium
batteries have. The high current draw shuts it down far enough above its suicide voltage to keep it alive. The motor shuts down at 5V and the voltage immediately bounces back to 9.5.

The receiver held up nicely in the drizzle. Had some spectacular saves as the nose turned in and the wind spooled up. As the nose-in hovers get longer and the altitude gets higher, it gets more exciting.

Taking a few more hops to higher altitude. Definitely experiencing more severe weather up there.
Posted by Jack Crossfire | Nov 03, 2006 @ 04:07 AM | 5,799 Views
11/2/06
28 min
94% humidity 60`F 5mph wind
250mA charge

27 min
7mph wind
2A charge

Harder to see the rotor in front of clouds than it is in front of the
stars. Doesn't feel like it's flying into space either when it's
cloudy. Easier to achieve nose-in forward flight than nose-in hover.
This time right turns into nose-in were easier than left turns. Nose-in
is starting to feel more comfortable but still can only hover for a few
seconds.

Hovering seems to take a lot more left cyclic when pointing nose-in than
when pointing nose-out. The tilt of the fuselage due to the lopsided battery is much more obvious when viewed from the nose, which makes it harder to see when the rotor is level and thus
achieve stable hover.

Hovering nose-out is automatic while hovering
nose-in takes serious concentration. Can now escape from almost any
situation into a stationary nose-out hover.

Hovering in high winds actually seemed to teach more than hovering in
calmer winds. At this point, in this weather, a co-pilot would have been a waste of money.

Successfully recharged at 2A for the first time. This particular
charger needs active cooling or it resets in the middle of the charge.
Still not confident enough to hover around the camera.

Could have made 3 flights but left the charger at 250mA after flight #2. Maybe next year.
Posted by Jack Crossfire | Nov 02, 2006 @ 01:44 AM | 5,435 Views
So with the rain officially underway, there will be few flights until June 2007 and you'll have to download something else. A note about Calif* weather forecasts:

Tuesday's forecast said 48 hours of rain beginning on Thursday. Wednesday's forecast said 72 hours of rain beginning Wednesday. How much you want to bet Thursday's forecast says 240 hours of rain? NOAA forecasts are based on a late 80's pattern of drought and don't reflect modern reality. If it says rain, multiply by 5 and move it up a day.

The last flight of 2006:
10/31/06
27min, no wind, temperatures in the 40's
250mA charge

Had good results flying 30 ft straight ahead, turning left to nose-in, and flying back. Turning right to nose-in was a different story, but managed to recover from every loss of control.

With freshly tracked blades and no wind, virtually no input was required to hover, definitely useful for nose-in. Seems to require lots of left cyclic when turning to nose-in. Sideways hover may be harder than nose-in because of the lack of sideways orientation information.

With throttle getting softer, entered a very stable hover 3" above the ground until speed controller shutdown and another smooooth Launchpad McQuack landing.

The Corona's tail whips around so fast, it makes the Comanche look like a '57 Buick. Could have used this in Iraq.

Abraham Lincoln wrote:
> Could have used something in Iraq.
Posted by Jack Crossfire | Nov 01, 2006 @ 12:14 AM | 7,004 Views
So the latest flight times with no lighting:

Sat 10/28:
30min high winds
28min * 2

Sun 10/29
28min * 3

Mon 10/30:
27min 20mph gust
26min

Flight times going down despite increasing winds. May be a loss of blade tracking or cold weather reducing the battery's effectiveness. Broke down and ordered a 4000mAh 11.1V 15C 275g Li-Po from maxamps.com ($94). Seems too good 2 B true. Our current 3300mAh 11.1V 20C 260g Li-Po was $120.

The weather is deteriorating as we enter the 7 month rain period in Rain Ramon. 20mph gusts during sideways hovering and category 5 during nose-in operations. Usually hits category 3 by the time the nose is 135` around.

Completely lost control while pointing nose-out and downwind when a 20mph gust happened. The tail started whipping around like a flag,
trying to point upwind and nose-in. Fighting the tail and pulling back caused it to shoot up like inflation. You see, without a heading-hold gyro, the nose naturally points into the wind.

Still shooting up with the throttle at auto-rotation speed and maximum aft cyclic. You see, extremely slow rotating blades provide no
cyclic authority. After some heroic flying, got enough category 3 wind to get it nose-out and pointing into the wind again. Collective pitch
would probably handle better in Rain Ramon due to the possibility of higher rotor speed.

In high wind, the $40 GWS gyro on maximum gain tends to snap the tail back and forth like a receiver glitch. Pretty exciting, in addition to the GWS receiver glitches. Still glitching despite wide antenna spacing and soldered crystal.