Kolibri's Korner -- a "blog" by a new RAF owner

[swilliams]

I've always had good luck with Advance auto parts in my neighborhood they have always seem to have had quality parts and back there warranty with out ever giving me a problem. Just my experience with my local ones.

Sincerely SWilliams

 

[Kolibri]

bugflyer, thanks, and I certainly agree with your point. I'll never pinch a penny when it comes to maintenance or parts quality. I'll look into a quality rebuild shop, but I hadn't the time this go-around.

There were cheaper remans than Rayloc, which I avoided. The NAPA guys didn't know who re-mfg the Bosch unit, and opined that it could very well be the same plant which do the Rayloc. They spoke highly of Rayloc, so I went with that.

If Bosch still mfg. this unit new, I'd have bought one.

I carefully inspected the Rayloc, and it looked new throughout. It comes with a lifetime warranty.
The VR is internal to these circa 1980 Datsun/Nissan 720 pickup 35amp alternators. Generic part # is 14231.

I installed it today, and went up for a bit, staying in the pattern.
Charging voltage was right at ~14.5. So far, so good.
It was quite cold, about 5°, and I reveled in the cabin heat.

Regards, Kolibri

 

[Kolibri]

202rrpm achieved with OEM RAF prerotator

202rrpm achieved with OEM RAF prerotator

I recently gyroed to a friend's ranch and landed on a 1000' patch of pasture that he occasionally uses for his TW. The takeoff next day had my full attention, due to a bit of roughness over ground.

On a hard strip, I use the standard RAF procedure: start the takeoff roll at 150rrpm, increasing power at 160rrpm, 180rrpm, and then full power at 200rrpm. This is easier on the prerotator system, and there's plenty of runway length to accommodate.

From my friend's pasture, however, I wanted to spin up to max rrpm before my takeoff roll. So, first, I serviced the prerotator clutch plate and pads (deglazed, and then scuffed up heavily), and readjusted the cable engagement. I got the clutch lever play just right, very firm, yet not dragging the plate. (A piece of paper folded 4x is about the right amount of space between the plate and pads. Make sure your plate turns true.)

After warming up the motor, I gradually prerotated to a max of 202rrpm (with a final ~1900erpm). This was the highest rrpm I'd ever seen, accomplished with a monster grip on the clutch lever. (At 200rrpm the rotor disk is very solid and no longer prone to flapping.)

I had about 8kt of wind right on the nose, perfect. The takeoff roll began a bit bumpy but I could feel weight quickly lifting from the mains which smoothened out the rest of the roll. I estimate that it took about 250-300' of roll to lift into ground effect, and I stayed there until 50mph AS (Vx). My friend texted me that the takeoff looked smooth and normal.

___
After nearly 2½ years of ownership and 200 hours of flight, I've some thoughts about my experience with the RAF2000. It's been an odd and unexpectedly uphill road, but on the whole I remain (generally) glad that I "went there". After a lot of mod/maintenance work, I am finally enjoying relaxed flight knowing that I've greatly increased its safety and reliability.

However, given that decent 1000' pasture, and my skill ample to the task, there should have been no reason for any apprehension about taking off from there. The apprehension was solely due to my understanding how tricky a takeoff roll the stock RAF can be, and needlessly so. It all went well, but I'm not fully satisfied with RAF's design and performance there. I'd like to be able to reliably spool up to 250rrpm, and roll with the stick full back without lifting the NW so strongly (or at all). Otherwise, I'm not getting even close to full potential of a gryo's short takeoff.

So, I think it's time for me to upgrade the landing gear (move back the mains, add suspension, and castering the NW). The RAF technique of balancing on the mains (to avoid touching a turned NW) I consider needlessly fraught with risk, and it increases takeoff roll since the somewhat flattened rotors can't spool up as quickly.

I'll also modify the prerotator (which may be due some new bearings, anyway) with a hydraulic slave actuator along the lines of what KennyJ did. RAF's cable and bicycle-cheap clutch handle really has got to go.

____
My general issue is this: with all the hundreds of RAF owners here and abroad, and the wealth of information shared by many of them on this valuable forum, you'd think that after a decade of new ownership by RAFSA that they would have incorporated at least some of our worthy mods. To date, there is still:

no geared redrive (cogged belt, what are we, the Flinstones?)
no main gear suspension, and widened stance
no castering NW
no differential toe-braking
no decent rudder pedals, which are also adjustable for pilot leg length
no improved prerotator system (e.g., a simple hydraulic actuator)
no superior electronic ignition
no long-lasting and lightweight exhaust
no safe/strong +500 hour life rotor system (head, torque tube, rotors, upper mast)
no control-independent trim system
no cabin-external fuel tanks
no H-stab
no lengthened keel to better keep the tail in the propwash, and reduce yaw
no vortex generators to reduce the wig-wag
no reduction in prop thrust offset
no improved seat belt attachement points
no improved cabin shape for aerodynamics and increased space
no engine cowling for improved looks and performance​

They've not even added a couple of idler pulleys to their p/r belt.

RAF owners have tackled all of the above (except for cowling and external fuel tanks) and almost all of our mods had been tested before RAFSA's purchase in 2007. Yet the Mocke family has incorporated none of them. And, as far as I can tell, they don't even manufacture the kits in South Africa — it's still the old Kindersley Canadians doing so, while you pay for the extra freight from Africa to help maintain the illusion of local RAFSA mfg.

Nothing has changed, yet RAFSA has the shameless gall to advertise their fusty, unimproved 1990s era machine as "modern" and "well-engineering" and "the best" on the market. Had they incorporated even a few of our mods, RAFSA would still own the USA LSA 2-place gyro market even if the kit were $15,000 more (which would include a Sport Copter system).

To close on a positive note, I think the 160hp Subaru 2.5FI remains a decent gyro compromise between power, weight, and cost. It's a water-cooled and heavier "IO320". From eddie's experience (and now others), it seems to accept a turbo well enough.

Regards, Kolibri

 

[Kolibri]

20170105 Kolibri parts list for the RAF2000

20170105 Kolibri parts list for the RAF2000

Some new items added (battery, alternator, etc.)

All text in green are parts I either found, or confirmed myself.

Regards, Kolibri

 

[eddie]

That's a good article, I would be happy with just a wider and little longer cabin.

And on another note there are two 2.5 Subaru's with turbochargers now,they are both

in my hanger @ Socorro,nm,my engine now has close to 700 hrs on it.I have a friend

that lives at a high elevation nearby and is enjoying the extra power provided by the

turbocharger.



Best regards,

 

[Kolibri]

history of my prerotator (which is still mostly stock)

history of my prerotator (which is still mostly stock)

Thanks, eddie. If I ever go up to a 2.5FI, I'd be tempted to also turbo it (at least turbo normalized).

_________
Here is what I've so far done to my prerotator system. Even though I've still the OEM cable, long shaft, and cheesy RAF clutch lever, when all components are recently serviced I can nonetheless get 200rrpm from a standstill.

Gates Green Stripe K060425HD belt (very heavy-duty)

two idler pulleys (90mm Gates #38019 grooved) (Gates #38002 4" smooth)

p/r shaft key slot and drive plate slot enlarged from 1/8" to 5/32"
(The larger key has lasted 50 hours so far, when I was getting <15 hours from the smaller OEM key. The drive plate also spins true now.)

Sport Copter upper mast plates (which are thicker, and also bolted vs. riveted), and flex issues should be a thing of the past. Any RAF owner can add these to his RAF mast and rotorhead, AFAIK.

Sport Copter Bendix, ring gear (Sport Copter recommends Mobil EM Polyrex or any NGL1), and rotorhead

lubed drive cable (Molygraph, per Sport Copter)

deeply gouged drive plate (as Harry S. used to do)

deglazed and scuffed up (use a flat file) pads

adjust for firm clutch lever, yet maintaining ~0.020" plate/pad clearance (use a piece of copy paper folded 4x). If the rotors begin to barely turn after you've disengaged the rotor brake before takeoff, you can sufficiently increase plate/pad clearance by loosening the clutch lever cable end (and it won't take much).​

I've not yet added:

shorter drive cable (51" on my SC rotorhead seems about right)
short p/r shaft (Harry S. recommends it)
brake pad material to the drive plate (several have done so here)​

The RAF prerotator drive unit does not seem to have a seal on the rear of the housing, and a bit of lube goops out the shaft into the pulley and plate. Does anyone else experience this?

____
I'm looking for a very high quality p/r clutch lever, which is flatter/wider under the hand than the RAF lever. I'd like it to be very well machined, and aircraft quality. (Perhaps it will have a cammed engagement.) If it requires rerouting another cable, I'll do so. (I think the RAF cable is too thin, anyway, and prone to stretching.)

Regards, Kolibri

 

[All_In]

Great thread about RAF's and I suspect the best one place to learn what to fix and improve.

You earn my U-ROCK award!

 

[Kolibri]

Thank, John! Well, I've learned a lot from folks on this forum, and am pleased to contribute back. Most RAF owners seem to be inherently making a "poor man's Cavalon" out of their modest ship.

 

[Kolibri]

I'm juuuust about to break 200 hours in my RAF. Since I'm more frequently visiting rancher friends and setting down in pastures and grass strips, I'm looking forward to improving the landing gear. I've an idea on castering the NW with an easy mod, and adding a "tiller" to steer it (as in airliners).

Regards, Kolibri

 

[Kolibri]

New forum format, wow, this is different, I wish it a great success. Just passed 200 hours in my RAF2000. Glad to have made it, and by now I know my machine very well. Speaking of RAF's, the SACAA (South Africa "FAA") just released their report on the crash of ZU-RHO. http://www.caa.co.za/Accidents and Incidents Reports/9462.pdf An extremely thorough 51 page report, and very damning for RAFSA. The SACAA now insists on helping RAFSA redesign the kludgy system since has failed to get it right themselves. Ouch. Regards, Kolibri

 

[Kolibri]

I just posted over at Microlighters some urgent info for all RAF owners, especially those in South Africa. http://www.microlighters.co.za/viewtopic.php?f=20&t=25762&p=240841#p240841

 

[Arizona723]

20170105 Kolibri parts list for the RAF2000

Some new items added (battery, alternator, etc.)

All text in green are parts I either found, or confirmed myself.

Regards, Kolibri

Kolibri, The list you have compiled is greatly appreciated. You have done a lot of good work on this.
I do have one item that you may know a part number for, that being the spark plug ignition leads.
Thanks,
Greg T

 

[Kolibri]

My pleasure, Greg, and thanks for the kind words. spark plug wires DirectImport, or was it ImportDirect? (#40275 - $27).

 

[Arizona723]

Thanks for the feedback. Mine must be different than most others. Original owner removed the individual coil packs and replaced with single electronic coil directly to distributor. Can't find wires long enough to go from distributor to plugs with 90 deg end at distributor. Wanted to find some good quality EMI leads to help with a little radio noise. Unable to locate original owner to ask if he made his own or found these.
Thanks again.
Greg

 

[Arizona723]

Decided to use MSD Street Fire and make my own.
Thanks Kolibri

 

[Kolibri]

behind-the-seat toolbag: $7 from Harbor Freight is their Voyager 11" toolbag.
Just the right size for an RAF. Black cotton 18 oz. canvas, with an external pocket for the most commonly used tools.

___
redrive bearings replacement: I R&R'd mine during its 2017 annual.
That service completes the last of my major sub-systems of the RAF 2000, so I can now say that after 3 years/225 hours I've gone through the entire ship.

RAF recommended replacement intervals:
The crank gear bearings (a pair of 6302) every 200 hours.
The prop gear bearings (a pair of 6207) every 500 hours.

The "V V" or "DD" suffixes simply mean 2-RS (two rubber seals).

"C3" is a particular clearance tolerance (and a rather tight one), so confirm such in new bearings.

The eight 8mm Allen bolts (black, not cadmium) of the crankshaft pulley are so close to 5/16 that I presume torque values are similar if not identical. I don't know if they're Grade 5 or 8. (Grade 5 bolts of 5/16-24tpi are dry torqued to 19 ft/lbs.) I could find no specs in the RAF Construction Manual. Mine were on quite tight, more than 19 ft/lbs (and probably close to 30). You'll need an extended 8mm Allen socket bit (Harbor Freight, etc.).

The crankshaft gear bearings have a standoff-plate bushing, and this was very tightly pressed in the double stack of 6302 bearings.

Regards, Kolibri

 

[Kolibri]

My latest RAF 2000 parts list is attached below, 20170514.

 

[Kolibri]

RAFSA owner Eben Mocke Snr walked into a prop last month and lost an arm.

This incident is a reminder to us all to pay very careful attention while working on a running engine.

 

[Kolibri]

I recently had the pleasure of meeting a new gyro enthusiast, who contracted with me to assist in a pre-buy inspection of an RAF Sparrowhawk conversion. Neither he (nor the owner, nor the previous owners, apparently) were aware of the failure-prone <2005 hub bar/winglets, nor of the Grade 0 control rod ends.

The prop pulley had a significant wobble, from either bearing failure or a galled pulley (which might be sleeved as a repair).

That such gyro had been flown for some 650 hours without incident is ex post facto relieving, but I cordially refused to flight-test the machine. (It was also legally nonairworthy being out of annual despite that the seller imagined his E-LSA Repairman cert valid to sign off on E-AB aircraft annuals.)

The purchaser seemed to take to heart my recommendations, and bought the gyro for a reduced price because of the work it needs.

I'm sure he will be posting on RWF as he goes through his RAF this winter, and will find, as I did, much invaluable info from our community.

_______
Earlier this year I dropped in to visit Jim Vanek at Sport Copters and enjoyed his brief and very instructive "recovery from unusual attitudes" flight tutorial. For just a few hundred dollars, you can learn from one of the best in the business, and fly (when available) a fantastic Sport Copter II. If you're ever near the Pacific NW, stop in Scappoose, Oregon to meet the folks at Sport Copter.

Regards, Kolibri

 

[Kolibri]

Next on my RAF will be a modified suspension and aftermarket ignition. Then, I think, I'll have completely all my major mods.
The 2.2 carb is running strong, with nearly zero oil consumption and full compression, at 490 hours.