There are also rumours of a wheeled undercarriage four wheel drive version of the 44...

The R4x4

😜

Cran now I feel much safer:E

for additional design ideas for RHC, here is a (sadly) long forgotten thread that is full of brainwaves!

http://www.pprune.org/rotorheads/209...inson-r88.html

Landing light globe failures
 

I know that Robinson now offers LED-type landing lights. This question is about the traditional incandescent landing light globes (which in the case of a Raven II would be two 28V, 100W, General Electric GE4591 bulbs).

We feel that these globes fail too often. In all cases, the filament is 'gone', sometimes with, or sometimes without, black charring inside the glass. But never is the glass of the bulb imploded or cracked, nor does the circuit breaker ever trip.

I tried to search this Forum for advise but couldn't find any thread that has dealt with this matter. Hence my question: What is in your experience the typical failure rate of these globes in a R44? And has anybody identified specific operating conditions that cause those globes blow more often?

Fix wing people indeed report (in this Forum and elsewhere) frequently the same problem. Admittedly, a broken landing light seems to be a much bigger problem for a fix winger, during any night landing. Whereby arguably in a helicopter, landing lights are not needed for safe night operations, provided you operate to and from landing sites that are equipped with "night flying facilities", which again in many legislations is a minimum requirement for any night ops (however, in case of night autos a working landing light would be a great benefit ;) ).

We only started keeping accurate records of this 'routine' replacements recently. Over the past 300 flying hours (engine Hobbs) we had 11 blown bulbs, with any one globe failing between 20 and 120 HRS after its last replacement. This is flying time, and the actual time with lights ON would me much less, although the lights get switched ON once during daily preflight (with engine OFF) and occasionally during flight.

The average life of a given globe therefore is around 60 flying hours. Practically that means (as the a/c has two landing light globes) that in average every 30 HRS either one globe has to be changed. (Only once though we had that both globes were blown at the same time.)

Is that still normal? :ugh:

I was flying scenics out in central Australia and if left on they would blow after a few landings.

Engineer recommended turning them off on approach as they overheat in hot climates at low speeds.

The LED ones are loads better they should be standard fitment IMO.

Turn off the landing lights before setting the machine down. When hot, it seems that the filament is less able to withstand any shock from setting down with anything other than a feather-bed kiss of the ground.


Not limited to R44; OP notes fixed-wing comment and I fly EC120. I think the LED option is to be preferred.

...or get more practice at landing gently :E

Not possible with a machine used for initial training (R44) or one where you are not the only pilot (EC120 Charter work)

Hi john,
Is the led light not available for the 120 ?
Although £24 for the front light isn't the end of the world when u need one anyways....
Did you know the same light was fitted to the 1970,s masey furgesen tractor ........

Nelly

Nelly - totally off subject; but do you know which model Massey had the same bulb?

(My father in law is a tractor buff and is convinced helicopters are the work of the devil... be nice to show him a link!).

C.

John - surely a student would only need the landing lights on for landing once he/she had the experience to land gently?! And I don't see why different pilots in a 120 should make a difference :confused:


Re HID/LED landing for a 120; I'd be interested in one of those too!

May not be possible with the R44, however, in light airplanes, if the landing light is installed (rotated) so that the filament is vertical instead of horizontal, the life of the bulb is significantly extended.

Thanks EN48, will give this a try.

As you already said, this is not possible in the R44. The bulb has a nudge, and there is a matching gap in the fuselage. So there is only one orientation (which is exactly horizontal) the bulb can be installed.

Actually, Robinson doesn't offer LED landing lights. Even the latest R44's come out with High Intensity Discharge (HID) lamps. LED is not an option, at least not on the RHC price list.

The conversion from incandescent to HID is possible, but it is not a 1-on-1 replacement, as an electronic ballast has to be installed.

Any experience how long those HID lasts in the field?

Try a Q4591 bulb. same bulb same size but is quartz halogen and has a flashlight type bulb inside the main glass...no flimsy filament to keep breaking. They are a lot more expensive (123.00 US Dollars) but they last for ever.

Edit: Its mfg by Whelen not G.E.

We had an engine overspeed on startup on R44 Raven2 ,normal cold start throttle closed,RPM went skyhigh .
Markings on fan nut out of line, technical intervention required.
Next on the same aircraft , cold engine starts the engine fires very good but when selecting clutch switch engine stops even before there is any movement of the blades.
Today on the same helicopter on warm start the RPM went very high again with throttle closed ,governor off,overspeed was just avoided.
Does anybody had simular experiences?

Sounds like you have some serious linkage problems on this one.
Better do a complete engine-throttle-mixture settings inspection.
Something moved there....

3top

Thanks, Paul, based on your feedback we shall now upgrade to HID. It is also exactly what Robinson replied a few days ago to my AMO on why they still don’t offer LED landing lights: They tested various LED lamps, none was as bright as the HID, and also they all were too hot.

I’d say, the latter is something to keep in mind when considering non-certified after-market LED upgrades.