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Brian DeFord

Members
  • Content Count

    27
  • Joined

  • Last visited

Community Reputation

10 Good

About Brian DeFord

  • Rank
    Member

Personal Information

  • Real Name (Public)
    Brian DeFord
  • Location (Public)
    Gilbert, Arizona
  • Occupation
    Mechanical Engineer
  • Bio
    Flying Cozy MK-IV N309BD - 'Blonde Streak'

Flying Information

  • Flying Status
    Flying

Project/Build Information

  • Plane
    Cozy Mark IV
  • Plans Number
    N309BD
  • Chapter
    Flying

Contact Methods

  • Website URL
    http://www.deford.com/cozy
  1. Brian DeFord

    required changes to increase speed

    Marc, I beg to ask for an explanation to that last part of your statement. Drag on an aircraft is a function of airspeed and as drag on an aircraft component increases, so will the stress that component sees (stress being the force (drag) over some area). It feels that way because it IS being pushed back harder! The parasitic drag produced by airflow over your hand is increasing as a function of speed. You weren't wrong...
  2. Brian DeFord

    Ac43-13b

    Try looking for AC 43.13-1B - I found it.
  3. Brian DeFord

    Citation 240 "TA" HVLP Sprayer / Respirator For Sale

    This item has been sold.
  4. I have a gently used (sprayed the primer on my Cozy MK-IV) Citation HVLP Sprayer / Respirator from Axis Products for sale. See the description at their website. I have the spray gun, hoses for both the gun and respirator, mask, belts and pump - everything that came with the unit. These are selling new for $1100 but I am willing to take $750 if you'll pay the shipping. http://www.axispro.com/index.php?categoryID=4 Brian DeFord
  5. Brian DeFord

    Panel pictures wanted

    This was my panel after installing the Trio Avionics altitude hold this past winter. Since then I have removed the Alpine CD player and opted for the MP3 input like Wayne mentions above. The audio panel has been swapped out for a PMA8000B with the music input on the front face of the unit. Also added but not viewable is a Garmin GDL69 weather datalink that interfaces with the MX-20.
  6. Brian DeFord

    Dynamic prop balancing - benefits!

    Oops - should say 51 grams not .51
  7. Brian DeFord

    Dynamic prop balancing - benefits!

    I just re-installed my Catto 3-blade prop after having the pitch increased. I thought this would be a good time to do a dynamic balance of the engine/prop combination so I set up the appointment for this morning. I've had a number of little items I've worked on for the past few months while my prop was in the shop, so I was busy this week getting everything in the engine area back up to snuff and ready for engine start. I finally got the prop back on, tracking straight and the spinner re-installed just as 8am rolled around and John showed up for the balancing. He installed his equipment on the top of the engine; an accelerometer to measure the movement of the engine/prop mass and an optical sensor to measure the RPM and clock the blades. A small computer uses the information from the two sensors to determine imbalance and recommend the location and amount of mass to add to offset the imbalance. After the sensors were installed I hopped in and started the engine. Blonde Streak hasn't had her engine run hard since January so I intended to baby her a bit. She ran real rough - more so than ever. After about a minute of this John told me to cut the engine and said he spotted some fuel leaking. We traced the leak to the new fuel flow divider I had installed - apparently I had only hand tightened the fuel lines at the flow divider and it was leaking from all four lines. We quickly solved that problem by tightening the nuts and then did a re-start. Much better! I let her run for about 5 minutes while the oil temps came up and then gradually increased the throttle until she was at max. I noted 2150 RPM and a fairly good vibration which I have been accustomed to since the beginning. I nodded to John and he took the readings on the machine and a few seconds later he gave me the signal to shut her down. The first reading was .69 inches per second - a little higher than John said he usually sees (about .4) but within the limits of balancing. John said the goal would be to get less than .2 and a reading over 1.0 is an indication of issues that needs more investigation before balancing is attempted. We were right in the middle of the range. The computer told him where to add the mass so he installed 3 large area washers plus an AN bolt and nut to the starter ring. I hopped back in a wen through the process again. A realized a very noticeable improvement in the vibration and the static RPM rose as well - this time to 2215! I hadn't expected that, but John said it's very common to see an increase in RPM after balancing. It makes sense - a smooth running prop and engine is going to take less effort to turn so the extra power is going to show up in RPM gain. Great! After the second run the reading came to .29 - still higher than the target, so we added two more washers to the same location for a total mass of .51 grams. I hopped back in, started her up and ran the engine up to 2270 RPM this time. Another increase and much less vibration again. After shutting down John said the reading was now .09 and good enough to stop. We removed all the sensors, wrote up the paperwork and made a logbook entry and called it a success. I'm thrilled with the results! Much less vibration and an increase of over 120 static RPM. The RPM increase was a pleasant surprise and one I'm grateful for. Since I had the prop re-pitched I knew I would see a drop in static RPM which would likely result in longer takeoff roll. The price you pay for higher top in speed with a fixed pitch prop. Well, the old prop used to run 2350 static RPM so I lost a net of 80 RPM so I'm not complaining at all. I know the top end performance will be better with the new prop and the smoother ride will be more enjoyable. I guess I'll have to go fly now to see if I'm right! Bottom line - if you haven't dynamically balanced your prop I would highly encourage you to do it right away. The benefits of the smooth ride, less wear and tear on the airframe and higher RPM's will translate into a much better performing airplane.
  8. Brian DeFord

    Cozy pic for wikipedia

    Heck, you can use any pics you find to your liking on my web site ( http://www.deford.com/cozy ), there are a couple of the completed plane in Chapter 25, or if you want a better picture than what you find, let me know and I'll take it.
  9. Just wanted to give a hearty recommendation to Craig catto of Catto propellers. As some of you remember, I had an airflow restriction on my IO-360 a couple of years ago that I just didn't know existed and I attributed the low power to an overly pitched prop. Craig will adjust the pitch for no cost on one of his props, so I sent it back and the difference was just what I needed. That is until I found the real source of my low power (the airflow restriction). I've flown about 20 hours since fixing the airflow restriction but the prop is obviously not pitched enough and I am constantly pulling the throttle back to keep it under redline. I spoke to Craig yesterday (11/28/05) prepared to buy another prop when he informed me he could adjust the prop back to the higher pitch! He didn't promise he could get everything back, but he said 100-150rpm was possible. Wow, I'd never heard of that before. So, first of the year I'm sending it back to be re-pitched yet again, only this time to get more pitch. I just thought that any of you looking for a prop ought to know that Craig is a great help and makes a great product. I'd highly recommend him.
  10. Brian DeFord

    Retracts w/Baggage Pods

    Gary's instructions have a BL 74 dimension for the centerline of the pods, but also says that the 74 isn't critical so long as both left and right side are the same. So, you could mount them outboard of 74 if it would make you feel better about the clearance. In any case, they are mounted on the wing, not the strake.
  11. Brian DeFord

    New canard aircraft wish list for Santa

    Here's my list: Mission: IFR cross country Performance: 250-300Kts Seating: 6 (2+2+2), single side door entry Cabin width: ~60" Gear: Fixed Single engine, deisel. Useful load: 2000lb - 1500lb (passengers+300lb baggage area) + full fuel (500lb ~70 gal) Cost: <$60k US materials (less engine & avionics) Plans built w/ quick construction techniques for airframe (<1000hrs)
  12. Ok, just suppose you could dream the perfect canard aircraft - what would you wish for? I'm talking about mission, performance, seating, cost, plans, kit or off the shelf. Secondarily, if the powerplant were a constraint would it be a single or twin engine? how about piston (deisel, avgas?), rotary or turbine? What about retracts? Let's assume you have a blank sheet of paper. If you want to compare it to a current design that's OK, just don't be encumbered by the past in your thinking. Who knows...Santa may be listening.
  13. Brian DeFord

    Retracts w/Baggage Pods

    No, the retracts are fully contained in the strake area I've got Gary Hunter's new pods for the MK-IV (first ones I think) and they mount to the wing. Mounting them to the strake wouldn't work because they require some hard points installed to capture the mounting bolts and you'd be jeopardizing the fuel tank area.
  14. Brian DeFord

    Copperstate 2005

    Ahmed Asif flew his Cozy N509MS in from California. So did Jorgen Skovbjerk in his Cozy N655DK both are pictures below. There were half a dozen LongEZ's and VariEZ's in attendance as well. The last photo is some of them grazing - sorry I didn't get details.
  15. Brian DeFord

    Copperstate 2005

    Added some pictures from Copperstate 2005. First one is of myself and the 3 littlest Blonde Streaks next to Blonde Streak after arrival. I had the fortune of having Cory Bird's beautiful Symmetry parked head to head with Blonde Streak. The next photo shows Symmetry in the forground with Blonde Streak in the background - much as it was all day! The crowds around Symmetry never let up. The next two are of Cozy N22AZ originally built by Robin Dubois. They were just leaving as I took the picture. Next is Doug Pitzer's Cozy MK-IV N433DP - a very pretty Cozy!
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