Funny how you need to have training and a qual. letter to climb a fixed, tethered structure, but there are no quals for a 100' mast on a moving platform.
Funny how things work out. The Friday before the SWE one of our ET2's gave tower training to the entire shop. While taking the test, some of the questions that were asked were some that were covered in the training. It would have been nice to have had some more obscure stuff covered. Look at it this way- for anyone who bombed the test- you have 360 days or so to study for the next test!
Were there any questions about tower lighting systems?
AC 70/7460-1K Change 2 is the most current information required by 47 USC 17 and is the guidance for tower Obstruction Marking and Lighting. It will discuss the various systems and the applicable standards for each system.
The publication is available on the internet.
BTW ... Loran aren't the only towers the CG inventory; they just happen to be the tallest.
Any temporary or permanent structure, including all appurtenances, that exceeds an overall height of 200 feet (61m) above ground level (AGL) or exceeds any obstruction standard contained in 14 CFR part 77, should normally be marked and/or lighted. However, an FAA aeronautical study may reveal that the absence of marking and/or lighting will not impair aviation safety. Conversely, the object may present such an extraordinary hazard potential that higher standards may be recommended for increased conspicuity to ensure safety to air navigation. Normally outside commercial lighting is not considered sufficient reason to omit recommended marking and/or lighting. Recommendations on marking and/or lighting structures can vary depending on terrain features, weather patterns, geographic location, and in the case of wind turbines, number of structures and overall layout of design.
The FAA may also recommend marking and/or lighting a structure that does not exceed 200 (61m) feet AGL or 14 CFR part 77 standards because of its particular location.
The latter paragraph illustrates the height can be anything depending on your distance from the local airfields.
CIM 11000.4A 9.E.2 states
quote:
The voltage at each lamp socket should be checked and to comply with FAA standards, may not vary more than 3% from the rated lamp voltage.
Advisory Circular 70/7460-1K states
quote:
44. INSPECTION, REPAIR AND MAINTENANCE To ensure the proper candela output for fixtures with incandescent lamps, the voltage provided to the lamp filament should not vary more than plus or minus 3 percent of the rated voltage of the lamp.
But you must remember, the lamps are not ordinary lamps .... as per CIM 11000.4 Chapter 9,
quote:
3. Provide the following lamp types:
a. Obstruction Lamps. General Electric, incandescent, 116 watt, A-21 bulb, clear, medium screw base, 120 volt, C-9 filament, 6000 hour. NSN 6240-00-842-2887.
b. Beacon Lamps. General Electric, incandescent, 120-volt, 700-watt, PS-40 bulb mogul pre-focus base, C-7A filament, 6000 hour. NSN 6240-01-030-7071.
c. Supply of Lamps. Each tower unit should always have on hand a sufficient supply to re-lamp their entire tower
As far as the tower identification, A leg, A face, etc ... here's what the tower manual shows
This message has been edited. Last edited by: JoeJester,
Stay positive cleetus, I think the test was pretty difficult for all. If seventy-five, which is the score the tests are all geared toward, was average we might have a shot. My buddy didn't post but got a 59. He's a really bright ET and the best trouble shooter I ever worked with, just not a great test taker.
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