Blade Tape Issues
 

I'm looking for some pictures of blade tape where the blade tape has been shredded by heavy rain and/or dust and sand. No attribution, just to illustrate problems with current tape.

had some pearlers from dessert landing training in El Centro, Cali. Il have a look for you

Could have taken heaps of photos years ago, not now, but suggest some may have experiences able to include incidents of little black beetles as well. Beetle causes a hole big enough to allow an inlet of high pressure air to lift tape from underneath right through to trailing edge of tape in V form. Also feathering and lifting on the trailing upper edge ends due dust vortices - can get bad enough to give a marked decrease in lift.

Shawn,

Be careful you don't "illustrate" too much as not all use is certified or "legal".

RVDT:
The legalities are an issue, but what I'm looking for are pictures to show where exactly the tearing of the tape occurs. It looks like it doesn't happen at the leading edge, but slightly aft of it.
No names, no pack drill as my old drill instructor used to say.

If you tear blade tape into 3mm wide strips and then wrap it round a 9mm. round where the extraction recess is it will build up a ridge that will hold the bullet nicely so it can be fired by a Smith & Wesson 0.38. Unfortunately it is not robust enough for the extractor to pull the cartridges out so you have to poke them out with a screwdriver.

It doesn't 'alf go.

Sorry Shawn... you're about 3 days late. I just fulled it all off, but you are right - never on the leading edge...?

It appears that the problem is that there will be small bubbles under the tape that are difficult to work out.
The rain going over the top of the blade creates significantly more suction than dry air, and pulls the tape up every so slightly, creating a small ridge.
This is enough for the air/rain to attack the ridge and rip the tape.
At least, that's the theory.

I always think these things (blade tape) cause more danger than any good.:8

How so.....?????
Point is....I've flown 21,000 + hrs. with 12,000 hrs on a longline, in a salt air laden, corrosive, erosive, heavy moisture, with snow, ice, and hail environment on everything from an asymmetrical blade to old style symmetrical (S64) main rotor blades with stainless steel and clear (3M) plastic tape, doing thousands of repetative lifts ( heli-logging) with absolutely no problems whatsoever.....please elaborate how blade tape is dangerous?????

I've heard stories of blade tape splitting and lifting that have made the helicopter virtually uncontrollable. Worryingly, the pilots didn't know the cause of the problem until after they had made an emergency landing.

Having said that, there's blade tape and blade tape. Some looks like little more than strips of Sellotape, whereas others are like Armorfend with sealant around all the outside edges and joints.

It concerns me that direct sunlight on the tape, when parked, may soften and damage the material and adhesive.

I'd be interested to understand the relative merits of blade tape.

Helilog
I simply say because of the number of incidents I've learned from, I have nerver operated an a/c with BT nor will want it as long as I can.
Since you have such vast experience with them, maybe you could enlighten us with some tips/advices/myths all about it.

The good thing about blade tape is you always know when it is coming off. Shaun, from the days of taping Bell 47 blades (almost daily) in the Australian Out Back - it peels off as you describe from the trailing edge. The aussies would also put hysol on the TR blade tips to stop the erosion.

Helilog56... like...what would you know? :)

We never used blade tape in the interior - not wet enough like on the coast where the loggers are pulling wood. Blade leading edges seem better and I think pilots are now more aware of adverse erosion conditions... like hail.

Shawn,

Not sure if its related, but for what its worth, when we went to Composite MRB's on the Sea King (UK Navy) with the metal leading edge, the erosion patterns were pretty clear, and I also recall that the butt straps (I think there were 3 per blade) used to lift at the trailing edge first.. We always used to put it down to lousy bonding.

Cheers
AA

Blade tape woes
 

I remember as a Plane Captain (grubber lad), we used to fit the clear tape over the black "Dunlop" tape as a matter of course when the blades arrived from the blade bay. because the cabs spent so much time in the hover over the sea during the cold war years (when metal blades were standard fit), it was a time saver to do it from fit. The tape was checked as part of the AF inspection and any lifting areas were replaced before they came too loose.
The secret was to fit the clear tape over good smooth Dunlop tape before any pitting or erosion had occured, this ensured a clean contact area and any bubbles were removed using the little wooden roller. The Dunlop tape was glued to the metal spar with Scotchgrip glue which could be replaced at the camp blade bay (yes I worked there too!), the use of MEK was necessary to clean the blade to replace the clear tape and paint stripper was used to replace the Dunlop tape (Oh those friday chemical headaches!)
We would hear the whip, whip, whip of a cab coming back with detaching tape and groan knowing it would add time to the AF, but not as much as changing a blade!
You often hear a similar noise from the Merlins but that is the wind whistling over the blade tie down socket in the tip.

Cheers now

Used to be amazing how much one could cut out of the tape if you got a small bubble or lifting of it and keep operating, just make sure about the same amount came out of the other blade. MEK was certainly the go to clean them.

I would suggest that a ridge or bubble on instillation was due to incorrect fitting, keen attention to detail was required. If you had spare it was better to start again, as long as the boss wasn't watching- not cheap that stuff!

Talk of temperature reminds me of operating in the hot climes in central OZ, at or above 50 degrees C the glue just would not hold and the tape would lift badly and dangerously quickly. Then of course the blade had to be thoroughly cleaned off of gum as anything going against you in that heat and D/A would make a hard life much harder. I don't remember if use of the tape had a temp restriction but if not I would suggest nothing above 45 degrees C.

I remember also seeing some tape the Israeli Army? -Air force? had developed and used, bloody heavy stuff- looked more like a deicing boot off a fixed wing. I don't recall being told what they put it on.

Blade Tape on Enstrom
 

In the days when EHC were using poly-3M tape on their Enstrom models ... that WAS dangerous, since I've experienced two forced landings which, in once case, rendered the instrument panel unreadable and in the other, cracked the base of the instrument pod ... I also suffered a third on a Hughes (Schweizer 300 - now Sikorsky) which forced me into a muddy field on a sales demo! Cost me a new pair of suede shoes! A fourth to Enstrom 280 G-LONS resulted in the aircraft rolling over following an attempted run-on landing and being destroyed. Pilot OK. The later stainless steel tape seems to have resolved the problem. EHC responded t the problem by putting tape breakups down to poor 'housekeeping.' Early indications on the Enstrom blade seemed to be discolouration and a yellow opaqueness. Most now fitted with a series of short lengths and flying with one section only removed involved very little increase in vibration and OK to get home. DRK.

that was a good input Dennis Kanyon, thanks for sharing it. :ok:

TAPE SAGA
 

Some time ago I arrived at a flying school to carry out an LPC in a Enstrom 280FX. they advised me they had a "bit of trouble" with blade tape, they had removed a piece of tape ( approx 300mm length) off one blade only.. I checked all the other blades and tape, they all looked fine to me, but I would have done all three blades he same. They said they had been flying with it ok.. I commenced the flying, the heli was flying pretty good , with only a small vibration due to rotor/ blade vibration/imbalance, certainly nothing unusual or abnormal for a Enstrom 280.. After 20 minutes carrying out low level exercises in the airfield, we done one circuit - all ok .
During the climb out on the second circuit, at approx 300 feet AGL, a heavy vibration started throughout the aircraft, -obviously from the rotor. At this moment I thought , this is too much for the student, I took control and thinking that I didn't want to continue , perhaps a 4/5 mile circuit, I turned right and right again , with the intention of coming back into the airfield ASAP. Almost immediately the aircraft entered a furious combination of REALLY huge oscillations, shaking and huge vibrations, oscillating in lateral, longitudinal and vertical planes. at this moment , I am not sure if the aircraft was moving around me, or was I going up and down in the seat, . make no mistake , at this moment the aircraft was now totally out of control.!!
It was impossible to to keep the heli in the air for one micro second longer, I entered autorotation, on the way down the vibration was so great I could not speak ( due my body being shook due to massive oscillations), I thought this has to be catastrophic, this is going to break up in flight!!!!! .. The area directly below us was some sort of crop, we had no choice, as I got of lower, it now looked like tall corn. we touched down very smoothly and by some miracle stayed the right way up.. we were now facing East, with a 10 knot tail wind, so we had landed downwind, we had a bit of a run on for 5 meters or so. When we stopped the "corn" was up to the temperature probe on the windscreen!- it was 5 feet tall! it was not corn, it was some sort of rushes.. As the blades were stopping , I could see a very large piece of blade tape hanging off - I would say it was 15/18 inches in length. I cut it off, and cut a similar piece of the other blades. After checking the heli over we started up and continued the flight. the heli was now flying A1 perfect!!.
A few thoughts on this incident,
a) on the way down it really was just a pure miracle that we stayed the right way up, -- I had no, or very,very little control of the aircraft..
b) I really cannot describe the vibrations and oscillations on the way down , other than to imagine , try flying with one blade off!!!
c) I have had blade tape come off countless times before, in many types of heli, most without incident,, but 12 years ago I did have a similar incident to this , again in an Enstrom - 280c, again it WAS out of control, but the forces and oscillations were very slightly less,* on this occasion, I felt the seat belt pulling and tugging at me on the way down , had it been undone I feel I would have been thrown thru the door!!
d) it was just pure luck there was a landing site below ( even if it wasn't the most suitable).
e) had the incident occurred above a non suitable landing site, i.e. town , houses, valley or forest the outcome would have been very nasty.

If you have blade tape fitted, check it, check, - check it again more thoroughly and then check it again!!

Final thought, blade tape, -- it really should be banned !!!!