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Del,

I’ve always used “Orange”  hand cleaner. Available at any auto parts store, or Home Depot.

Try it!

Cheers,

David Williford

Yup, Fast orange.  Or Nitrile gloves…stop the problem before it starts.

-John

Fast Orange.

This may not be canard related but I get my hands dirty working on my Cozy. I have always used Boraxo powdered hand soap but apparently it was not so safe and it has been taken off the market. There is one 5 lb. box on Amazon but $180, give me a break.

There seem to be many brands of such thing but Boraxo worked so well I would  like to find a substitute. GoJo never seemed to work and I hated the smell. Boraxo even too the epoxy off my hands.

Any good recommendations

Del Schier

Cozy N197DL

Cannon Creek Airpark 15FL

?

Folks:

In the latest (today's) Squadron III Newsletter, put out by David Orr, there's a section called "Non-Builder Owner Advice", which says, to quote:

"... If you put a video camera out on the winglet, for example, it might be grouped in the Major Change category, requiring a 5 hour fly off – you can do it where you are, right? No, the only place the plane can go back into Phase 1 testing is where the area was designated originally....

So unless you are close to where the plane was first flown... Problem is when you want to move that test area, you have to get your Op limitations reissued with a new test area ...

I am guessing that changing the weight capacity of the airframe – perhaps in exchange for reducing the “Gs” it can take, I’d bet the FSDO would consider that a major change. And so many of the builders made their planes heavier than the designer expected so if they didn’t say a word about testing to a particular weight – you have a deep row to hoe...hope you get 5 hours that you ask for.'

---------------------------------

There are a number of serious errors in the above. One at a time (and all this assumes you're in the USA - other countries will/may have different rules):

Firstly, the determination of what is a "Major Change" is made based on the definitions in 14 CFR Part 21.93:

A “minor change” is one that has no appreciable effect on the weight, balance, structural strength, reliability, operational characteristics, or other characteristics affecting the airworthiness of the product. All other changes are “major changes”.

So putting a camera on the wing, unless it "appreciably" affects the characteristics listed above, is NOT a Major Change.

Secondly, you NEVER re-enter Phase I testing period, no matter what changes are made (Minor or Major) to a flying E-AB aircraft. This is a common misconception that we've discussed here before. What the OL's require is a 14 CFR Part 91.319(b) compliance test period - this is NOT another "Phase I".

Thirdly, the Phase I test area applies only for Phase I - it is NOT required for any subsequent 91.319(b) test periods. The OLs will clearly state what you need to do to get a 91.319(b) test area approved, if any approval is necessary. You do NOT have to return to wherever that plane's Phase I testing was performed - this is really bad advice and incorrect.

Fourthly, unless you have very old OLs that invalidate the AC in the case of a Major Change (and those OLs haven't been issued in over 30 years, so any planes newer than that will NOT invalidate the AC) you do NOT need to get new OLs issued - all you need to do, usually, is get your LOCAL FSDO to approve whatever test area you request (and you will work with them to ensure that you request something they'll approve).

Lastly, while changing the MGW of the aircraft, assuming that the MGW was ever listed anywhere in the aircraft's documentation (which MAY be in the W&B, but isn't always) is most certainly a Major Change per 21.93, the only thing required, in almost all cases, would be a letter to the local FSDO stating that you'd like a test area of <X> for a retest of higher weights. Once you get a written approval of your test area, you log entry into the 91.319(b) test period, go test your plane for the required time period (almost always 5 hours, but could be more) and log the exit from the test period with the verbiage suggested in the OLs. It will be very rare that the FSDO will give a FF what the change being made is - only that you test it in an area in which if you crash, you don't kill anyone other than yourself.

None of this is particularly onerous, nor restrictive.

I hope this clears up some of the egregious errors regarding regulations and requirements listed in the newsletter.

Does anyone have direct experience (or just an educated guess) to suggest what thickness and size of Kevlar skid plate might be enough to withstand a gear-up landing and preserve the nose?

Has anyone had a gear-up landing with a kevlar skid plate and shown that it will, in fact, "preserve the nose"? I'm not convinced - while it's crap to sand and bulletproof, it can fairly easily be ground into dust with a dremel tool, and it doesn't take a lot more work that grinding fiberglass or carbon - it just leaves a ridiculously fuzzy surface that's a bear to fill/sand. Unless someone's got some test results indicating lower wear than metal or wood products, I don't know that I believe it would be substantially better, if at all.

 

I realize that heavy-duty rubber has proven to be effective but I would like to consider all material options, and maybe even a combination.

So here's (from an engineering standpoint) what my idea of the perfect nose skid/bumper would look like (and I have NOT figured out a way to implement this - I tried, after my last gear up landing two and a half years ago, but failed miserably to do so).

• The bottom would have a sacrificial and easily replaceable rubber layer that's used as a bumper, per the plans, so that the plane doesn't skid around on the ground when parked. Although I have to admit that the metal (steel) nose gear "feet" also seem to work well, at preventing sliding motion, so a metal plate with sharp edges might be as good as a rubber bumper.
• Under the rubber (well, above it, but you know what I mean) would be a sacrificial and easily replaceable skid material, such as the aluminum that Wayne Hicks used (but never tested) or wood as used on SS1/SS2.
• Under (again, above) the metal/wood would be a crushable material. This would have the ability to deform and absorb energy so that when the nose slammed into the ground in the event of a gear up, there would be minimal impact damage to the nose sides - there have been numerous instances on COZY IIIs, Long-EZs and COZY MKIVs of the fuselage sides cracking and deforming forward and aft of F-22 due to impact. I figure that a 1" crush zone would be more than adequate, as it would eliminate >90% of the impact load impulse.

This is asking a lot and as I said, although I got some AL honeycomb to try to use as a crush zone, I was not able (in a reasonable time period) to come up with a solution that included all of the above, wasn't fragile, and looked semi-reasonable.

So here's what I've got:

https://www.mcmaster.com/catalog/130/4075/8634K48

You might take a hint from Burt Rutan as they use a good grade of hard oak.  Mike once told me any good HARD wood would do, as there are several woods that have a hardness higher than oak.  I know ironwood and zebra-wood are right up there.  Over the years their have been several nose gear up LDG's using a HARD wood and saved the fuselage from damage.

 I suspect the harder and denser the wood is, the slippery it becomes as Nat thought using the puck also somewhat kept the plane from sliding to much.  I don't know how he came up with that as hockey pucks slide pretty well.

Anyway , you can take it from the master himself in that he used oak wood substituting for the nose wheel on Space Ship One as shown in the pic below.....      Vance Atkinson

https://www.falkenavionics.com/

https://store.falkenavionics.com/products/falken-ems-stand-alone-version

https://www.falkenavionics.com/falken-ems-sensor-guide/