TARMAC
The Official News Letter
Of The
September 2001
Your Executive Officers
| El Presidente |
Andrew Parr |
479 3235 |
| Vice El Presidente |
Chris Todd |
833 5841 |
| Secretary |
Martin Seay |
525 6505 |
| Treasurer |
Peter Cole |
473 0130 |
| Committee |
Anton Lawrence |
813 6404 |
| Committee |
Willie Morton |
025 901 796 |
| Chief Flying Officer |
Willie Morton |
025 901 796 |
| Safety Officer |
Niol Lockington |
817 5959 |
| PPAB |
Peter Nicholson |
625 4010 |
| PPAB |
Gordon Swan |
827 5089 |
| PPAB |
Vern Booth |
360 4016 |
| Editor |
Anton Lawrence |
813 6404 |
Web copy of TARMAC
http://kirstant.orcon.net.nz/Armac/Tarmacs.html
Official ARMAC Web Site
http://www.acomodata.com/armac/
Next Club Meeting, 3rd Tuesday of the month.
September 18th
At the Pikes Point Airpark Clubrooms 19:00
Committee Meeting at 18:30 Sharp.
Editorial
Spring is sprung the grass is riz I wonder where all them birdies is.
There will be plenty of flying going on now the sun has managed a two day weekend.
Allex and I had a nice fly from Thames to Te Kowhia in a Cesna and then flew his Bantam back to Thames, all before lunch. There was lots of activity at Te Kowhia and I'm sure there would have been some at Pikes Point, so come on lets hear about it.
If you have anything in the trade and exchange section I will leave it there until I hear it's sold or until it's been there long enough.
At the next meeting Gordon Swan will give a talk on maintenance methodologies.
Anton Lawrence
Anyone interested in some GA flights contact Ross Glover 576 6884
Prez Sez
A short one this month, firstly congratulations goes to Martin Seay for obtaining a rating in the Maverick based at Te Kowhai. It is also noted that John Struthers has bought an S6-Coyote. I'm sure we all wish him many hours of happy flying.
The club/syndicate bantam is now sporting a new wheel for the trolley, which should now be easier to pull in and out of the hanger.
The BBQ at David Rees is still going to happen, but has been put on hold until the weather warms up.
And finally a reminder to instructors. YOU MUST BE AUTHORISED to instruct from Pikes Point by either of the club committee's. If not, you have been warned and will now face disciplinary action if caught. Those who are currently authorised by A.R.M.A.C are Willie Morton and Niol Lockington. If you wish to be authorised please apply to the committee. It should be noted that if there is a need for specialist training i.e. type ratings an instructor maybe brought in for such a task provided that the individual has obtained prior approval from the C.F.I (Willie) or if he is un-contactable the president or safety officer.
Andrew
THE USE AND CARE OF YOUR LODESTONE.
By Jon Farmer.
Over four thousand years ago the Chinese knew about a form of iron ore called Magnetite or Loadstone that had the property of attracting other iron ore and also could be made to point towards the South. However, they just seemed to regard the phenomena as a novelty and it was not until about 600 BC that the Greeks made crude compasses by floating splinters of loadstone on bits of wood in a bowl of water. Around 1750 the first fully documented compass appeared in England but it had an iron needle that had been magnetized by stroking it with pieces of lodestone and it turned on a metal pivot. Soon after this the British Admiralty formed a Compass Division and knowledge of the Earth's magnetism and compass design progressed rapidly. It was established that the Earth's magnetic pole could be as much as 25 degrees away from the North Pole, or True North, and that this 'Variation' changed slowly such that, at London, it has gone from 15 degrees East to 23 degrees West and is heading back to 15 East, the whole cycle being over about 500 years.
A few years ago, the CAA in their wisdom decreed that ALL microlights must be equipped with certain minimum instruments, including a compass. This brought protest from some aircraft owners and one of our members showed his disdain by fitting his compass half way down the rear fuselage. In his case this is perhaps warranted, as the aircraft is of a type that would only be flown in fine weather and probably within a 20-mile radius of its home airfield. Another of our members set off on a cross country from Pikes Point to Matamata via Te Kowhai. Leaving Te Kowhai on a hazy morning when the Kaimais were not visible and having to go at right angles to the direct route until clear of the Hamilton Control Zone, he became disorientated (lost you might say) and had to land to ask the way. Ok, he did the right thing in the circumstances but lets have the benefit of hindsight and set off from Te Kowhai with a flight plan.
In Figure 1 is reproduced a section of the Auckland VTC (Visual Terminal Chart), which everyone who flies from Pikes Point should have. If you get cited for a violation of Auckland or Hamilton airspace it would be akin to putting your head in a noose to put forward the fact that you did not have a VTC as an excuse. Anyway, it is a handy map as it covers from Kaipara Harbour and Logan's strip in the North to well below Matamata in the South on a reasonable scale (1:250,000). You can see that Hamilton control zone is in the way of a direct flight from Te Kowhai to Matamata so draw a course that clears the zone and goes to a position that should be recognizable from the air, in this case where power lines pass a sawmill, then another course to Matamata. Measure the True courses and the distances in nautical miles. Convert the true courses to compass courses and calculate the time your aircraft will take on each leg. On takeoff from Te Kowhai turn on to your compass course and note the time then add the expected time on this course to get the ETA at sawmill. This is called 'Dead Reckoning' navigation and will get you very close to your destination on trips up to about 100 miles. If your course is incorrect by 5 degrees you will be 5 miles off course after 60 miles but if you are only going 12 miles, you will only be 1 mile off course, which is not a great distance by air.
To read a course off the map, a 'Douglas combined protractor and parallel rule' is very handy. It consists of a 12cm clear plastic square marked in degrees, 0 – 360, round the perimeter and a grid pattern over the remainder with a matt finish that you can write on in pencil. My old one cost 7shillings 6d and a newer one was $1.80. Set the small centre hole over your point of departure and, using the grid pattern, line up 0 degrees with a meridian of longitude then read off your course. To measure distance, mark off the matt portion with a scale of miles taken from the vertical scale of latitude where every 1minute of latitude is equal to 1 nautical mile. DO NOT MEASURE DISTANCE ON THE HORIZONTAL LONGITUDE SCALE, as along the Equator is the only place that will be correct. Now convert the true course to magnetic by looking for the variation on the title part of the map, in this case 20 E. There are all sorts of mnemonics for applying Easterly variation to a true course but another way is to draw a thumbnail sketch as Figure 2 with a compass card offset 20 degrees to the East of true (Variation to the East) then mark in the true course and it will quickly be obvious that the magnetic course is going to be less than the true. i.e.: 044 T. – 20 E. = 024 M. Your compass course will be the same as the magnetic if you have an all aluminium or fiberglass aircraft and the compass is not too close to other instruments otherwise you will have to apply 'Deviation' to magnetic course to get the compass course.
Compass error or 'deviation' can be found with the aid of a hand bearing compass or other reasonable quality compass that it is possible to sight over. Set the aircraft in flying position, which means lifting the tail of a tail dragger, and swing it around until, sighting from behind with the hand bearing compass, it is pointing North Magnetic. If the error or deviation is less than 5 degrees make a note of the reading and if greater than 5 degrees, correct by placing a small bar magnet near the compass at right angles to the compass needle, that is athwartships, adjusting the distance until the compass reads North. Use a small blob of plasticene to hold the magnet in position until adjustment is complete. Then swing the aircraft round to East Magnetic and again correct with another bar magnet at right angles to the compass needle or fore and aft this time. Swing onto South and adjust the athwartship corrector magnet to take out half the error then swing onto West and take out half the error. Do another swing but stopping on NE, E, SE, S, etc and noting the residual deviation. Draw a thumbnail sketch to determine if the deviation is East or West. If your compass has built in correctors you are bound to either do a full compass swing and correction or remove the built in magnets. For a professional adjustment you should have the engine running with enough RPM to be charging the battery as the magnetic fields round the wiring might affect the compass.
If you are going to purchase a compass consider how much you expect to use it, the value of your aircraft and the degree of sophistication of the instrument panel. You can obtain a neat looking compass from an auto accessories shop for a few dollars or a very good quality marine compass from a marine store or a second hand aircraft compass for a price between the previous two. Remember it is very hard to find a position where you can look down on a compass in an aircraft cockpit so go for an edge reading type. The best compass I had was a 'Silva' brand marine compass in the form of a 6cm clear plastic sphere with the card marked on top and round the edge. It's pivot rested on the inside of the sphere, rather like a top, and so it didn't matter what angle the aircraft was, the card was horizontal. I mounted it in the instrument panel along with the altimeter and VSI neither of which had any magnetic material in them worth mentioning. When flying my single seater I wear a diver's wrist compass and find it quite convenient to take bearings with as well as keep a check on my heading. So, please don't rubbish your compass – use it sometimes when you don't need it and you will be glad you did when you do need it.
Trade And Exchange.
Private owners only
Contact the Editor to place an add
813 6404hm 025 354 998wk
kirstant@orcon.co.nz
Trike,FXN, current air cert, plenty of instruments, long range tank, rainbow wing a pleasure to fly, low engine hours, $3,800.00 neg contact Alex; 09 5366815 h or 09 5342190 e-mail atocollision@paridice.co.nz
Koenig "Pagojer" 18 Hp 3 Cyl radial engine, with prop, cage, and harness for powered 'chute. In good condition, reconditioned a few hours ago. $2000. Further details from: BRODIE ANDREWS, ph. 8175433"
Warpdrive three blade 58"-60" left hand ground adjustable prop. Older type with two sets of hub plates to suit either standard Rotax 75mm or 4" bolt pattern for VW or Subaru. Moulded-in metal leading edge protection.
Never been used. $900 Contact Jon Farmer, ph (09) 520 0641
Icom A22 handheld radio, 760 com: channels plus VOR navigation readout. Alkaline battery pack. Brand new in box $950
Contact Jon Farmer, ph (09) 520 0641
Two quality Peltor headsets, intercom with cables for connection to Icom radio and push to talk switch. All new. $650 the lot or I can fit the headsets with standard GA plugs and sell them separately. Contact Jon Farmer, ph (09) 520 0641
Intercom, with connoectiions to radio $200 Contact Jon Farmer, ph (09) 520 0641
Helmets with clip on peak and Peltor earmuffs. Fully adjustable for size. Wear a beanie underneath in cold weather. Either red or blue. $180
I can customise these helmets with speakers and microphone to suit your requirements. Contact Jon Farmer, ph (09) 520 0641
Dac and ¼ share of Hanger No.3 at Pikes Point.
Dac has only 5 ½ hours airtime, recovery chute and many extras.
Make an offer for aircraft and hanger together or separately, but aircraft must be sold before hanger goes separately. Contact Brian Mcleod, 351 Weber Rd, RD1 Dannevirk 5491. Ph 06 374 6635.