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Messages - marc22181

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1
Hangar Flying / Wiring a Second com without an audio panel
« on: March 05, 2008, 07:11:36 AM »
I just did that.  If you have an intercom, all the required wiring runs to it.  Get a 4pdt switch from digikey or mouser electronics.  You'll see 12 contacts in three rows.  Find the wires that run to the intercom's ptt input, mic input and audio input.  put those wires and the common ground on each of the center row terminals of the switch.  Run one side (row) , in the same order, of the contacts  to the original radio, the second  to the number 2.  If you don't have an intercom, use the wires that run to the headphone and microphone panel jacks instead of those to the intercom.
good luck,
Marc

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Hangar Flying / Lowering Stall Speed
« on: February 22, 2008, 09:34:34 PM »
if the main wing is modified to provide improved
characteristics and would reduce landing speed significantly, say ten mph,
is a corresponding and equal modification required to the canard?


Bill,
It depends.   Lets talk stall speed, but its really angle of attack that makes the difference.  

As a thought experiment, lets say you make the wing stall at 10 kts.  The canard still stalls first-at 50 kts or so, so the possibility of a deep stall is avoided.  Now in effect, the aircraft stall speed remains limited by the canard, but a wing with substatially reduced stall speed should produce greater lift at slower speed than the same untreated wing.  Therefore the approach speed can be reduced a bit (still 50 + reasonable margin) without experiencing the sink you might currently get at very slow approach speed.  On the other hand,  to truly take advantage of whats done, the canard stall speed should also be reduced, but never below that of the wing.  That can be done in several ways.  The two easiest are changing the canard angle of incidence or adding lift enhancing devices ie. vortex gens, flaps, slats etc.  The micro vortex generators treat both the wing and canard.  I'd be interested in any first hand experience with them.  

Quite frankly, I'm very reluctant to play with the canard angle of incidence.  I think one could get into very serious trouble with that.

3
Hangar Flying / Lowering Stall Speed
« on: January 25, 2008, 05:39:42 PM »
If I approach at 60 I won't need any runway.

4
Hangar Flying / Lowering Stall Speed
« on: January 23, 2008, 02:12:29 AM »
Bill,
Many thanks for your well thought out response.  I agree that the stall angle of attack is pretty much fixed for a given wing(s) configuration,  as you point out, increasing gross weight adversely affects stall speed.  The problem is most, mine included, 0320 equipped, IFR longeze's weigh in at over 1000 lbs.  With two on board and reasonable fuel, 1600lbs  is pretty much the norm.  That means the stall speed is well above the original longeze design.  Bottom line, other than making it a one seat aircraft, lots of kinetic energy is dissipated in the roll out.  Techniqe can make shorter fields available, but in a real off field emergency, you want a little extra energy and the brakes are not going to do much good in slowing you down. In that situation, the airframe is the brakes.

That's basically what prompted the question.  The Mike Price VGs sound interesting.  Are the Price vortex generators the same as the micro VGs?

I wonder if anybody has thought about a drooped leading edge like all Cessna 172s went to a few decades ago, or for that matter some kind of flap or drooping aileron configuration.

Some years ago, California Microwave and another outfit (can't remember their name) built up some LEs for use as UAVs  One of them had extended wings for high altitude flight.  That would be a pretty extensive retrofit.  That is unless there was some value in extensions beyond the rudders.  

Any further thoughts?

5
Hangar Flying / Lowering Stall Speed
« on: January 02, 2008, 08:09:08 AM »
I very much appreciate the comments from all.  My rationale for posting this was primarily safety and secondarily making smaller fields available.  In the first case, touching down at 50 Kts vs. 60Kts represents a decrease in energy of 31% as the energy goes as the square.  In an off field landing thats pretty significant.  In a short field landing, thats a lot less pressure on the brakes.  I completely agree with the need for proficiency, but for a given level of proficiency, lower stall speed (AOA) is always good.

The vortex generators and trailing fences sound good.  Is there a web site for the vortex gens?   I've seen the fences on the verieze, does anyone have dimensions and locations for the long?  Do the fences increase lift or just improve aileron performance?  

Has anybody tried high lift devices like leading edge cuffs or drooping ailerons?

Marc 770EZ

6
Hangar Flying / Lowering Stall Speed
« on: January 01, 2008, 06:08:13 PM »
RE: how much reduction am I looking for...I'd be happy with 5 kts, very happy with 10.  
Marc 770EZ

7
Hangar Flying / Lowering Stall Speed
« on: January 01, 2008, 11:14:35 AM »
I'm looking for ways to reduce approach speed and runway requirements.  Has anybody had success with lowering the stall speed of a longez?  Micro vortex generators claim a 9 knot reduction, but if that's real, I'd think lots more folks would have them installed.  It would be interesting to hear if there are any ideas or better yet history with devices or airframe changes to improve low end performance.

Marc
770EZ

8
Hangar Flying / removing the bolt through NG6
« on: December 08, 2007, 07:03:16 PM »
I tried changing the brass NG6 bushings, but can't get past removing the bolt.  The head turns, the nut comes off, but the bolt doesn't slide out.  Even hammering it doesn't work.  I don't want to break anything, but did give it several dozen whacks.  Any advice would be greatly appreciated.  
Marc
LE N770EZ

9
Hangar Flying / I'm looking for the drawing(s) of the longez tie down points
« on: October 04, 2007, 07:40:43 AM »
I'm looking for the drawing(s) of the longez tie down points referenced in the plans change section (CP-24) around page 5 or 6. I have the text from the cozy web site, but would really like to see the drawings attached to it.
Thank you,
Marc
LE 770EZ

10
Hangar Flying / help with tie down hardpoint
« on: September 25, 2007, 05:44:06 PM »
Drew, Bruce,
Thank you, but I was really looking for the original long ez tie down attachment as described in CP-24.  I know its not as clean and neat as the retractable, but I'd just as soon not remove the attach bolts and would like the tie down points farther out on the wings.  I was hoping to  get the sketch from cp24 or a better description of the location coordinates .  

Marc 770EZ

11
Hangar Flying / wing tie down hardpoints -need help
« on: September 24, 2007, 08:45:27 PM »
I found the text of CP-24 that describes tie down hardpoints and also found a similar description on the cozy website.  The CP dimensions of "13" inboard along the leading edge, and 9.5" aft of the leading edge." Seem to put the hardpoint on the shear web.  From the Cozy site, "Measure forward of the trailing edge and perpendicular to it 12-3/4" does seem to put the hardpoints aft of the shear web.  Which is correct and where exactly are the measuments from?  The leading edge from inside the winglets or outside?  I thought the LE and Cozy had the same wing.  Are dimensions perpendicular to the Leading edge or Trailing Edge?  A drawing or better description would be very helpful.

Thank you,
Marc

12
Hangar Flying / Whelen Lenses are made of glass!!!
« on: September 15, 2007, 10:26:58 AM »
Did that too.  Aircraft Spruce stocks them.
Marc LE 770EZ

13
Hangar Flying / Vortex generator installation
« on: September 03, 2007, 07:35:16 AM »
Drew, thank you.  The pictures on your site were very helpful.  Stay safe in Iraq..Marc

14
Hangar Flying / Vortex generator installation
« on: September 02, 2007, 02:37:33 PM »
I'm about to install vortex generators on my long ez.  The installation instructions that came from CCI were somewhat vague.  The canard is almost 12 feet long, but 100 vortex generators spaced 1" apart is only about 8 feet.  Are they supposed to be centered on each side? Should they favor the outboard ends?  Also, the thickest part of the airfoil appears to be about 2" forward of the 50% chord line.  This may be my imagination, but it does seem forward if the elevators and canard are both used to measure chord.  Does anyone have a measurement from either the trailing edge of the elevators or the canard elevator cutout line.
Thanks very much for the help.
Marc

15
Hangar Flying / IFR training in a long
« on: January 24, 2006, 07:04:06 PM »
Your question is interesting and while a long ez is a perfectly reasonable IFR platform (especially so with an autopilot) it does pose several challanges.  For one thing, there is not a great deal of room to spread out charts and plates, but planning can overcome that.  Another issue is training.  As a CFII, I must admit that I wouldn't be comfortable a an instructor or safety pilot in the back seat.  I don't think the visibility is sufficient, nor do I think the standard stick only would allow me to take control sufficient to prevent problems in many circumstances.  If for example, you were nearing ILS minimums and another aircraft cut in front, I wouldn't have a throttle to provide maneuvering power.  I wouldn't have any instrumentation, so I couldn't even evaluate your performance on the glidepath or localizer.  I wouldn't have comms with ATC and so on.  Suggest you get your training in a more roomy aircraft with full dual controls for the instructor.  Also, you can just sit in the cockpit and work out chart storage, map folding and IFR checklist proceedures.  A lot can be done on the ground.  If you feel completely comfortable on VFR cross country flights and comfortable in IFR in a spam can, then start doing some IFR flights in VMC.  After that, you're good to go.
Marc

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