search.noResults

search.searching

dataCollection.invalidEmail
note.createNoteMessage

search.noResults

search.searching

orderForm.title

orderForm.productCode
orderForm.description
orderForm.quantity
orderForm.itemPrice
orderForm.price
orderForm.totalPrice
orderForm.deliveryDetails.billingAddress
orderForm.deliveryDetails.deliveryAddress
orderForm.noItems
MAINTENANCE MINUTE


By Scott Skola Blue Light Special (Part 2): Our blue light special on tips continues from your last issue of Rotorcraft Pro...


Tip #4 Calm Needle Jitters Ever struggle to match engines because the torque indicator needle(s) are oscillating back and forth? Before digital systems became the norm, some direct reading systems such as the BO105 were notorious for this.


A fluid (engine oil) does not physically compress like a gas (air). External or internal anomalies can influence the pressure flow to the torque indicator and cause the needle to fluctuate. A quick way to cure this, or troubleshoot the indicator, is to install a “shock absorber” in the oil flow. Disconnect one or both torque lines at the back of the indicator. Pull them away from the indicator and drain the oil from each line into a rag or container. Reconnect the lines.


The small pocket of air captured between the oil-filled indicator and the system oil flow will compress and absorb the intermittent pulses of pressure change while maintaining a constant pressure indication.


If after several attempts the needle(s) still fluctuate, further troubleshooting may require installing a direct reading gauge at the engine side, or installing a replacement indicator. However, the culprit could also be an indicating system flex line that is collapsed internally or kinked, causing the oscillation.


Tip #5


Let it Out Note: The tip is valid only under several conditions: the aircraft has Apical floats; the float system has integral life rafts; and the inspection/repacking of the floats is complied with by an external third-party vendor.


After complying with an actual inflation test on a line aircraft, it takes forever to deflate all the floats with the single test adapter found in the inflate-deflate kit. Until now.


If you look on each inflated life raft, you will find a perfectly good test adapter stuck in a strap of material attached to the side of the raft. Now if by chance those extra adapters were “forgotten” in a toolbox after the float assemblies were routed to a vendor for inspection and repack, I would bet several inflation tests later, one would have enough adapters to dramatically speed up the deflation process.


Tip #6 Brass Tactics Back when the only intake filter option for an AS350 Arriel engine was the bleed air type, it was a pain to leak-check the engine because the cowling had to remain installed with the filter bleed air line connected. There supposedly was a factory cap for the bleed fitting on the engine that enabled removal of the cowling/filter assembly, but neither we nor the tech reps could ever procure one. We did attempt to fabricate a cap similar to the pressure caps used on MBB products, which consisted of a proper sized “B” nut with a steel ball bearing nestled in it to seal at the fitting flare. Except these “B” nuts were special order and it was hard to justify destroying a $500 bleed air hose just for the fittings. Then entered an enterprising machinist (photos below). It’s made from brass to allow ease of machining and provides a sacrificial mode in case someone tries to cross-thread it.


24


Sept/Oct 2018


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92