Long-EZ Stolen in Ohio

[mak790]

But flying at 1600 lb (275 lb, or 20% above DESIGN MGW) turns a 5G airplane into a 4 G airplane - still above "Normal Category", but below "Utility Category",

Marc,

I was wondering where is that 5G's comming from (was it only example?), I've never seen any official source of G load for Long Ez, but some people claims that G load for Long ez is about (I've seen different opinion) 11-12G. I understand that they were rather talking about ultimate G load, so if you divide it by safty factor for composite structures 2.0 (1.5 for metal planes) you will get about 5.5-6G. One thing is clear these planes aren't as strong as some people might think.

http://www.cozybuilders.org/Canard_Pusher/RAF_LE-Structural-Test.pdf

 

Seb

[JLKnolla]

Marc,

I was wondering where is that 5G's comming from (was it only example?), I've never seen any official source of G load for Long Ez, but some people claims that G load for Long ez is about (I've seen different opinion) 11-12G. I understand that they were rather talking about ultimate G load, so if you divide it by safty factor for composite structures 2.0 (1.5 for metal planes) you will get about 5.5-6G. One thing is clear these planes aren't as strong as some people might think.

http://www.cozybuilders.org/Canard_Pusher/RAF_LE-Structural-Test.pdf

 

Seb

Thanks for that article, real eye opener although too many unknowns (previous cycles, previous loads, any history of overstress or damage, age, environmental, workmanship, etc.) to make a definitive decision IMO. As I recall, RAF did some extensive structural tests on fresh LE wings and canards and the results (if memory serves) were very impressive.

[mak790]

As I recall, RAF did some extensive structural tests on fresh LE wings and canards and the results (if memory serves) were very impressive.

Two questions:

What is a definition of "very impressive"?, and second question who built those wings and canard? average builder or some professionalists.

 

Seb

[Marc Zeitlin]

I was wondering where is that 5G's comming from ...

The V/N diagram in the Long-EZ POH. (Which, if you examine it closely enough, is extremely inconsistent, so it's almost impossible to know what the REAL design loading is).

 

And don't tell me to ask Burt, as if no-one has thought of doing that before.

[JLKnolla]

Two questions:

What is a definition of "very impressive"?, and second question who built those wings and canard? average builder or some professionalists.

 

Seb

As I recall failure reportedly occurred in the 12+ G range using leadshot bags, think they may even have ran out of lead initially.

 

Since the moldless foam core construction method was essentially new for aircraft use at the time I would think it might be hard pressed to call anyone 'professionalists' at the time but it was certainly the folks at RAF who had built several planes at that point I assume.

 

As Marc and others are quick to point out, with something like a thousand examples flying now and untold flight hours, no accidents of the Long's have been attributed to inflight structural breakup (if built to plan anyway).

 

Structural failure at 7-8 G's is a big deal compared to the 12G number I remember reading somehwere, although 8G's is still a good margin over normal operations and even mild aerobatics at the plan weights or maybe even a little heavier (not doing the math right now).

 

When Dick and Melville flew their record flights their birds weighed almost 2500lbs reportedly, or put another way, half a ton over the design weight. Certainly didn't do any aero at those weights, but the planes flew for extended periods at high weights.

[mak790]

 

And don't tell me to ask Burt, as if no-one has thought of doing that before.

Don't worry I won't.

 

Seb

[Lynn Erickson]

 

 

I'll be very anxious to see how these changes actually affect the flight characteristics of this bird.

it will feel heavier, longer take off, slower roll but pitch sensitivity will be about the same. you can feel even 20 lbs. increase.

[mak790]

although 8G's is still a good margin over normal operations and even mild aerobatics at the plan weights or maybe even a little heavier (not doing the math right now).

Yes but you have to multiply it by 2.0, which means 16G ultimate not 12G. Anyway it seems that only Burt knows real numbers. Here is a good example of the Boeing 777 wing load test, it broke at 1.54 so it means 0.04 above what was required, incredible.

http://www.youtube.com/watch?v=pe9PVaFGl3o

 

Seb

[TMann]

Waiter ..... just curious, did you happen to get an empty weight prior to your retrofit project?

I know these planes have a habit of gaining weight after the first flight.

New electronics, extra cushions etc. It could be you did not have as much weight gain as you thought.

 

In any case, I'm looking forward to your flight tests. You have eliminated some substantial drag.

[Drew Swenson]

Waiter....Did you forget to subtract out the ballast that you used to weigh down the nose while on the scales?

 

You aren't carrying 2 full size batteries are you?

[Waiter]

Drew, I used a 25lb ballast when I weighed. Also had 10 gallons of fuel on board. I pulled both these weights out of the gross.

 

I do have two batteries on board, The original Oddessy (PL940???) and a small Sonic (4 lbs - for the second Electronic Ignition)

 

Waiter

[Drew Swenson]

Waiter....I was nearly 100% that you pulled those weights back out....just making sure there was not a simple error you may have overlooked.

 

Pretty sure that you use a spreadsheet for wt and bal. Double check that you did not erase or miscalc something by mistake. This is probably not it either. One of my troubleshooting motos is to always check the easy things first----which I also know you live by too. But sometimes when you get too close to the problem, you forget the easy stuff.

 

The extra weights you mention won't put you over the top. Do you have a lot of nose ballast that you can remove with a longer nose? Are both batts up front? Is the weight of the main gear taking up all that extra weight?

[Waiter]

The weight was read right off the scale, minus the fuel and temporary ballast. No calculations (love those scales)

 

I don't currently have any ballast, but I may need to add ten lbs in the nose to pull the CG forward an inch (currently at 104.5)

 

Waiter

[TMann]

Is the weight of the main gear taking up all that extra weight?

The Gear weighs around 72 lb with the pump. #2 lb per leg plus 10lb for the pump.

Subtract the fixed gear bow from that and you start to get close to the difference.

[longez360]

Wow, that's probably a 60lb delta! I did not realise the infinity gear was that heavy.

 

When I first built N360WZ I had a full dual electrical system for a planned flight home from the USA to Australia and it was heavier than I had planned. This posed untenable limitations on flight operations. I had dual electronic ignition systems, and without much thought assumed dual electrical systems would provide redundancy. I was incorrect. When I realised the primary failure mode for the ignition systems would not be mitigated with another battery and alternator, I got rid of the 2nd electrical system (and removed one of the ignition units and added a magneto). Given I was in the weight reduction game, I also changed to a wilhelmson retract system (from an alternate electric retract system), and pulled some other non-essentials. The first flight after this large weight reduction was an ENORMOUS improvement. This was the largest performance gain I have seen in my aircraft with all the modifications I have made, all rolled up in handling characteristics and climb. Now I just need to lose some weight... :-)

 

I often dream of a rock stock 800lb Long EZ with a good O-360. What a weapon it would be to fly! It would be an absolute rocket ship.

[longezdave]

I don't currently have any ballast, but I may need to add ten lbs in the nose to pull the CG forward an inch (currently at 104.5)

 

Waiter

Have you done something in your mods to change the aft CG limit?

[TMann]

Wow, that's probably a 60lb delta! I did not realise the infinity gear was that heavy.

Closer to 40lbs

[Waiter]

The published Aft limit for the LongEZ is 103.0

 

I'm at 104.0 now, so I'll need to add 10lbs at FS at FS-5 to move the CG forward to 103.0.

 

Attached is the spreadsheet I used in the calculations.

 

You can also find this spreadsheet on my web site.

 

Waiter

LongEZ_Weight_and_Balance.xls

[mplafleur]

Hurrah for Waiter!

 

Will be standing by for taxi/flight test reports.

[Waiter]

INITIAL TAXI TESTING;

 

The ride is noticiably rougher than the original gear. But also noticiably more stable; The nose doesn't bob, and the plane doesn't rock.

 

Brakes - WOW. I can lock up the brakes and skid the tires. (couldn't do this with the original Clevelands). Brakes are firm and very responsive (I attribute this to the two puck Matcos and the use of 1/4 inch solid line, (no more Nylaflow). I haven't tried full throttle with full brakes yet. With the Original Clevelands, the plane would creep forward as the brakes couldn't hold it. I'm guessing that the plane will now skid forward. (constant speed prop)

 

 

WEIGHT GAIN ANALYSIS;

 

Adding systems to the plane adds weight, and has negative effects on some aspects of the aircrafts performance.

 

Hopefully, the added system (and weight) also improves some aspect of the aircrafts performance to offset the negative impact.

 

In October of 1996, My EZ weighed in at 950 lbs,

 

Upon completion of my rebuild, I again weighed my EZ, this time it came in at 1180 lbs, What contributed to this 230 lb increase in weight?

 

I've included an analysis of the weights and systems added since the aircraft was weighed in 1996. These weights are reasonably accurate estimates and should provide an overall picture of what systems contributed to the weight gain.

 

 

I primarly use my EZ for long distance, high altitude travel.

 

 

The three items that I fell were overwhelmingly worth the weight are the Constant speed prop (37 lbs), the Oil Heat system (23 lbs), and the NavAid autopilot (15 lbs)

 

 

The largest single culpret in the weight gain is the Retractable gear (98 lbs). Although the subject of performance differences between retractable vs fixed has been beat to death, In this particular application, I prefer the retractable gear. As I start flight testing, I'll post more regarding preformance.

 

 

Waiter

N961EZ_Weight.xls

[Waiter]

Heres a PDF version of the spreadsheet:

 

Waiter

N961EZ_Weight.pdf

[Lynn Erickson]

Heres a PDF version of the spreadsheet:

 

Waiter

It is going to be interesting to see the new performance figures. this is one of the few plane to get the mods after it had flown many hours and has some old numbers to compare with. The gear will make the biggest difference, it will hurt the climb rate the most but still should be a good performer with the CS prop and the extra 10 HP from the FI. Thats a lot for the oil heater but worth it where you are living now. I tell new builders to figure 100 lb. increase for the retract gear but most of them always try to tell me it will only be 40. This helps clear up the 40 lb. myth. top speed should be a bit better. the gear should make 10 MPH difference and the extra weight should not make much difference at top speed. the CS prop will slow down the top speed over the fixed pitch prop. I think you will feel the weight in the stick but you won't really care because it is flying again. it is what it is, no going back now so enjoy the flying and have a safe test session.

[TMann]

I tell new builders to figure 100 lb. increase for the retract gear but most of them always try to tell me it will only be 40. This helps clear up the 40 lb. myth.

That's a bit odd, Lynn. You yourself should know what the gear weighs.

32lb per leg ........ okay, that's 64. Now another 10 for the pump ........ that's 74.

 

......no, I can't say as I can buy 100 lbs. And that's not counting the fact that you subtract the bow.

 

You'll never get a guest appearance on Mythbusters with that kind of workup.

[Waiter]

TMann, I was also taken a little surprised at my numbers. but they don't lie.

 

Glasswork, i.e Just the reinforcement pads inside the Centerspar weigh 3-4 lbs each. Then throw in the wheel well inserts and extra flox/glass to make them leakproof. the neat little shelf in the nose that the pump sits on, gear doors, etc.

 

Plus the plumbing, I figure I have five hose assemblies in each wheel well, (10 total) plus three more at the pump. These are all quality hoses with steel fittings. I estinate each hose weighs about 3/4lb, plus all the interconnect tubing, plus the strut valve.

 

Then throw in the sensors, controller, switches, wiring, etc.

 

All those little inconsiquential things that don't weigh anything start to add up. :-(

 

I wouldn't have believed the tradeoff would be close to 100 lbs until I seen the numbers!

 

Would I do it again, Yup. If you want to play, you gotta pay

 

Waiter

[Lynn Erickson]

That's a bit odd, Lynn. You yourself should know what the gear weighs.

32lb per leg ........ okay, that's 64. Now another 10 for the pump ........ that's 74.

 

......no, I can't say as I can buy 100 lbs. And that's not counting the fact that you subtract the bow.

 

You'll never get a guest appearance on Mythbusters with that kind of workup.

I don't want to turn Waiters thread into a gear pissing match. i do know. we pulled out 105 lb. of stuff out of the aero canard and the spar lay ups are still in there. as for the true weights, there are some that can say they have been there and done that and the new builders that will find out. if the gear weights 74 lb. for the pump and legs. you can add at least another 35 lb. for the controller, hydraulic lines, solenoids, oil, hoses, switches, emergency down system, hardware, extra glass for the wheel wells, extra structure and gear doors, bigger wheels, bigger brakes and bigger tires. as Waiter's weights show, when you make mods the weights add up faster then you can count them.