Schofields Flying Club Ltd - 1 Tower Road Bankstown Airport 2200
(PO Box 200, Georges Hall, NSW 2198 AUSTRALIA)
Phone: +61 2 9773 3611 Email: mail@schofields-flying-club.com.au
SCHOFIELDS FLYING CLUB NEWSLETTER - AUGUST 2006
Welcome to the August 2006 edition of Schofields News.
Jabiru VH-LSN now on line
There are the usual plus some new features -
President's Notes by Mike Allsop,
Jabiru J-160 Inbound by Peter Cunningham,
Ask the ex-CFI by Rodney Hyde,
X-File X065 (Savoia-Marchetti S.M.91) by Anthony Coleiro,
Flying the Tin Shed (Part 3) by Craig Hobart,
28 Years Between Flights by David Jaffray,
Darwin Flyaway (Part 2) by Bill Larkin,
Jabiru VH-LSN now On-line by Sheri Crawshaw,
Jabiru Familiarisation & Approval Programme,
Wayne's World by Wayne Russell, and
Last Word from Latrodectus. As well, there's the usual administrivia that you've come to expect. So, read on and enjoy!
NEW MEMBERS FOR JULY: Welcome to Chris Parkes, Dave Ryan, Brendan Dove and Michael Leung.
JULY DUTY PILOT DRAW: The Volunteer Duty Pilot Monthly Draw ($50 free flying) for July will be announced in the September Newsletter.
FROM THE TOWER: The August/September edition of the Bankstown ATC news circular has been published. This is a bi-monthly source of news and information to keep you informed of interesting and important events happening in and around the airport. Download your copy HERE (244kB pdf).
DIARY DATES: The Club has a number of social and flying activities planned for 2006. You can check full details on our Coming Events page. Below is a summary of the programme for August and September 2006:
| Sun | 06 | August | Club Competition | Warnervale |
| Mon | 21 | August | Committee Meeting | Clubhouse |
| Sun | 27 | August | Last Light Drinks | Clubhouse |
| Sat | 02 | September | College Presentation Night | Clubhouse |
| Sun | 17 | September | Club Competition | Warnervale |
| Mon | 18 | September | Committee Meeting | Clubhouse |
| Sun | 24 | September | Last Light Drinks | Clubhouse |
Mike Allsop
What a miserable month for flying we have just had! Most of our weekends have been a washout for cross country flying, and it wasn't too flash for circuits either. Mid-weeks have been equally uninviting for the most part. Given the amount of water lying around our parking area last week we should be asking BAL to offer us a floatplane jetty.
There has been a bright spot however in the arrival and induction into service of our new Jabiru J-160, VH-LSN. Our Treasurer Peter Cunningham flew it from Archerfield in company with Glenn Cannell, Qantas Training Captain, owner and specifier of the fit-out for this version. Glenn helped the first batch of our instructors to become familiar with the aeroplane in an instructional context, and others will come up to speed on it very quickly. Overall, this has been a very professional induction process at the operational level.To introduce our Members to the aeroplane we have prepared a basic fact sheet and have scheduled a Workshop Program and dual instruction package to familiarise as many as possible in a fun group environment. More detail can be found elsewhere in the newsletter and on the website. To help those without email or internet access, we are also mailing information out. We anticipate that there will be strong demand for this fun, affordable yet sophisticated aeroplane. Make sure you get your name down for the workshop program if you can. If not, self study and Club assessment is still available, and a pre-requisite to flying this glass panel aircraft. Members who have not flown for quite a while are especially welcome - it's not just for the regulars!
VH-LSN, the Club's new Jabiru J-160 On other matters, Peter Kestle is carrying the role of Chief Pilot / CFI, reporting to our General Manager John Lowing. Peter will still perform the "HAAMC" role in overseeing our fleet maintenance for the time being. Peter has extensive multi-engine and IFR training experience, and you should feel welcome to discuss any requirements or interests you might have in PIFR and CIR training with him.
On the multi-engine front, our regular Duchess IPH is off getting new engines at present. In the meantime we can use other aircraft on the field for multi-engine training purposes. Remember too that Aztec PFD is available for those interested in 6 seat capacity and comfortable long range operations. It's a real beauty.
Several of our instructors are able to provide multi-engine training and single or multi-engine IFR training. If you are looking to upgrade, or if you are in the midst of your CPL and want these services, make sure you give either Peter of John a call to discuss. Or talk to your instructor!
We had a very successful Night Circuits event on July 28th, popular as usual with over 20 pilots taking part. We will try to squeeze one more in before the days get too long. Also, for those with a night rating make sure you get your short night cross-country experience requirement in place while we have a window of good weather and early nightfall. A quick one hour / 100NM flight can be a great deal of fun as well as being a NVFR requirement.
Finally, just to remind you that not all flying is carried out horizontally, Chris Pearl is keen to hear from you if you would like to learn about (very) unusual attitudes and aerobatic manoeuvrers. The Cessna Aerobat is a cheap way to get this experience in a familiar and forgiving aeroplane before (or if) you want to move up to a dedicated aerobatic machine like a Decathlon or a Pitts. Give it a try!
Let's hope August is a better flying month for us all, and make sure you join us at the Jabiru events coming up.
Mike Allsop
President SFC
Peter C'ham
It was a sunny morning with little wind to speak of when I boarded an 8am burner for the 1 hour 20 minute flight to Coolangatta where I was to collect the Jabiru for the return flight to Bankstown. The departure was from 34R on the ENTRA 2 SID and after levelling off at 5000 feet beneath the Approach corridor, we encountered moderate chop and I thought to myself that this was not going to fare well for the return trip to Bankstown.
However it smoothed out on climb and before I knew it we were on final approach into Cooly. Glen's brother Grahame met me at the terminal and we walked the half km to VH-LSN which was parked on the GA apron where it was already attracting a steady flow of interest.Glen was going to conduct some promotional flights prior to our departure until a call from the avionics people suggesting that, if we flew to Archerfield, they could fix the transponder. In the meantime Grahame was stockpiling parts to be loaded into the Jabiru for the trip to Sydney. It seemed there were enough parts to build another one, including tyres. But given the baggage area can only hold 36kg we did leave some things behind.
Glen arranged for someone to lodge a flight plan from Coolangatta to Archerfield and inform the tower the transponder was U/S. No problems, and we soon were taxying out and heading for Archerfield at max speed.
VH-LSN, the Club's new Jabiru J-160 The arrival at Archerfield was uneventful and after having the transponder serviced and the aircraft refuelled, the pilots watered, fed and de-fuelled, we lifted off at 12:15pm for the non-stop flight to YSBK. I am still learning to apply back pressure at 40kts during takeoff otherwise the thing tends to drunkenly weave down the RWY. (I forgot to mention that we needed to re-submit a flight plan and, having no facilities readily at hand, Glen called his daughter in Derby WA and asked her to submit it for us. We know the plan went in as Briefing called us to clarify the details!)
Glen flies here so he knows the area well and we set course on a southerly heading to leave via the lane. Once established outbound we attempted to put the flight plan into the GPS but we were both learning the system and it would not quite accommodate our requests. Over our discussions I thought I heard Archer Tower call us and suggest we take up an easterly heading. After the second more urgent call I was sure it was for us and the instruction was "turn east now, you are heading into a Restricted Area."
Oops! Full left rudder and maximum angle of bank saved the day. I can only dread of what spurious label they attached to the TAAATS Radar paint in Brisbane Centre.
Back on track and OCTA we climbed to A055. We settled into a routine and I started to investigate the many features of the glass cockpit. After a short period the FMS and engine management system were fairly easily mastered. The GPS functionality was a little bit more difficult to grasp, although no more so then the GNS430 in the other Club aircraft.
Approaching Coffs Harbour Glen and I established we would enter controlled airspace on our direct track to Port Macquarie. The GPS has a nice little function that will advise you at a time prior to penetration to enable a clearance to be obtained. Obviously Brisbane were on to us because just as the alarm went off, they called to advise that the aircraft abeam YPMQ would shortly enter controlled airspace. Well fancy that we replied, we assume you have our clearance organised. Reluctantly they cleared us direct Kempsey at our present level.
Ferry pilots Glen Cannell and Peter C'ham Our next challenge was to navigate through the Williamtown Control Zone. It was active with 'Cobra' aircraft looking for something to shoot down. But we figured they were more interested in getting home and heading for the bar then intercepting us. Again the GPS showed the inland transit lane through Willy which would have been quite handy had we needed to use it. As luck would have it after initial difficulties in contacting them, we were cleared through their airspace and on to BBG.
From BBG to Prospect was familiar territory and approaching PSP quarry I was about to call inbound when a Baron piped up calling inbound. Well that caught our attention. Neither Glen nor I could see the Baron so I wheeled the Jabi (that's what ATC call them) towards BK and just as I was about to call inbound, Glen spotted the Baron behind us. So I let BK know it was behind us and proceeded to a 3 mile final for RWY 11. Bankstown asked if we could accommodate the Baron to land ahead of us as it was apparently quicker. We did not spot the Baron until just inside 3 miles and Glen thought we may have to go around. When Glen spotted the Baron to starboard it was barely crawling past us which must be shameful for a Baron to be struggling to pass a Jabiru. With nearly all the power off and arms flailing we got the thing configured for landing and were cleared to land just as the Baron exited the RWY. Not the best landing I have ever done but that will one of the new challenges in mastering the Jabiru 160. After the long taxi to the Club we were greeted by some of the members who anticipated our arrival around 5pm and we delivered her at 4:55pm, ahead of schedule.
The Jabiru is a different kettle of fish to the conventional GA aircraft and you will need some type training on the beast. The Club is preparing a package to convert you to the Jabiru covering the "Glass Cockpit" and flying component. Otherwise you can just try it out with an approved Instructor to get the feel for it.
One final thought before signing off. Don't get too involved or absorbed by the "Glass" in the air or, as you can see, you can easily violate controlled airspace or potentially conflict with another aircraft. Get sorted out on the ground and if you are unsure with any of the systems, seek help from your instructor.
I enjoyed flying the Jabiru and I know it will offer a new and exciting experience for everyone.
Peter Cunningham
Treasurer SFC
Rodney Hyde
G'Day All. It was strongly suggested that I should write an article for the clubs newsletter on my experiences in the Maldives. Well, I believe I hold the record for the longest time to complete my training and be checked to line. At this point I would like to point out, its not because I was excessively slow, the company is desperately short of training captains. It took 25 days to get 5 days of flight training in.
I came to the Maldives to fly for "Maldivian Air Taxi" (or MAT for short) who operates the DHC-6, the De Havilland Twin Otter on floats. The aircraft are operated with two flight crew and a cabin attendant and up to 18 passengers. The company MAT, leases the aircraft and flight crew from Canada. Fortunately for me the Canadian company is having trouble supplying enough flight crew to fulfil their contract. Apparently pilot employment prospects in Canada are very good at the moment, causing pilot shortages. The last four new pilots to be employed here have all come from Australia. Interestingly there are no flight training schools in the Maldives, so they must import all their pilots.
Maldivian Air Taxi - (MAT for short) I had never flown turbo props before or operated in a two crew environment, so despite my experience, it was a steep learning curve. This silly aeroplane just would not stay still for me. It would roll or pitch whenever it thought I was not looking. Pitch changes on flap extension would then balloon you up +200 feet even after you lowered the nose some +20°. The ailerons were so heavy that I thought I would need to go to the gym. In short I was very much the student once again, well outside my comfort zone.
If MAT was in Australia then it would be considered at least a regional airline. MAT is the largest domestic operator in the Maldives with 20 aeroplanes. Induction flight training at this level consisted of the training captain demonstrating the particular sequence, be it approach to the stall, steep turns or any one of the emergency procedures, then you have a try and get the sequence right. Then try again to get it within tolerance.
Do you remember in your own flight training when your instructor was always pushing you to maintain your height, heading or airspeed? May be this is still ahead of you as you prepare for you flight test? Below are the flight standards as per the Day VFR Syllabus and the Airline like standards I have just been assessed against.
| PPL Standards | CPL Standards | Airline Standards | |
| Altitude * | ±150 feet | ±100 feet | ±100 feet |
| Heading * | ±10° | ±10° | ±5° |
| Speeds * | ±10kts | ±10kts | +10kts, -5kts |
| *= Day VFR Straight & Level Standard (not IFR) | |||
For all the pilots out there aspiring to greater things, try within yourself to achieve the next level up. Push yourself to improve your own flying or better yet get your flying partner (that person who normally sits beside you when you go flying, may not even have a pilot's license) to help you. In a multi crew cabin the non-flying pilot monitors these tolerances and calls either "altitude"; "heading", "speed" if you deviate beyond those tolerances. There is no reason your flying partner can not be briefed to point these out to you especially when you are clear of busy airspace. You will be amazed just how quickly this will improve your flying, for you can not even begin to fix something if you do not even realise it needs fixing.
During my final check ride a flight inspector from the Maldivian Civil Aviation Department (CAD) was onboard to observe the check ride. I managed to lose 100 feet on the prop over-speed drill and was made to do it again. These flight tolerances may be easy in straight and level, but when you can maintain them during other flight manoeuvres and emergency drills, you are ready to steep up to the next level.
Good luck and safe flying to you all.
Rodney Hyde
ex-Chief Flying Instructor
Considered Italy's answer to the de Havilland Mosquito, the S.M.91 was a two-seat multi-role aircraft designed to do the work of a long-range escort fighter, interceptor, reconnaissance-fighter and fighter-bomber. Fulfilling the Italian Air Ministry's further specifications, for considerable operating radius and heavy forward firing capability.
Savoia-Marchetti S.M.91 The S.M.91 was an all-metal twin-boom aircraft with a crew of two seated in tandem. It was powered by a pair of 1,290 hp Daimler-Benz DB 605A-1 12-cylinder engines. For armament, three 20 mm cannons were placed in the nose and two further cannons were placed in the wing roots. Provision was also made to carry external stores.
The aircraft made its maiden flight on 10 March 1943 and at 22,965 feet, attained a speed of 515 km/h. Only a limited amount of testing had been completed before the Germans evacuated Italy after the signing of the armistice with the allies and any further development was halted. Only one prototype had been produced.
ACKNOWLEDGEMENTS
- The Complete Book of Fighters - William Green Gordon Swanborough
- War Planes of the Second World War Fighters Volume Two - William Green
CONTINUED FROM LAST MONTH...
The departure gave us an opportunity to see Birdsville from the air. The race track is on the edge of town, quite a walk actually, although what's the rush? I understand buses trundle to and from the pub all day for the punters on the first Saturday in September.
The flight to Broken Hill saw us covering more desert country, over Moomba, which was pretty busy with aviation traffic; a Cessna conquest was descending from the north east, a BAe 146 descending from the south, plus a few smaller planes as well.
Ore pile on South Road, Broken Hill With the current resource boom, dishwashers make $120,000 a year!! This is putting a real strain on other sectors of the economy, namely ruralists who can't compete with this industry. Perth also has problems filling many roles; the money is drawing people up to the mines.
The descent into Broken Hill was again an opportunity to fly a RNAV approach. The last few miles took us over mountains (hills really), something we hadn't seen in days, for a landing straight in from the north.
The GA parking here is half a mile from anything, I wondered why this was the case; given all the space out there it really didn't seem necessary. I borrowed a trolley from the airlines to load our stuff and headed for the budget counter where we were given a Toyota Avalon, a Japanese car made for America!!
Before heading into town we walked over to the Royal flying doctor base - and what a great place to visit!! We spent an hour of so looking around and being shown through the facility by a helpful volunteer and finished by decking out the family with Royal flying doctor gear.
Desert sculptures The time in Broken Hill was memorable with great views from the top of the slag heap in town, a visit to Silverton the ghost town where Mad Max was filmed, and the sculptures of the desert on a hill a few miles out of town.
The family loves trains and Broken Hill has a significant train museum right in the middle to town, so we enjoyed taking the boys through there. As fate would have it a vintage car rally finished at the Museum so we got to view some of Australia's best vintage cars for free!
The rest of the time was spent driving the heritage trail around the town - which takes hours! Not helped by a couple of local pranksters who had us following arrows out into the desert?
We dropped into Pro Hart's Gallery, and had a great milkshake at the local in South Broken Hill, as well as dropping into see the golf course, with no grass and black greens!!
Then it was time to head east again and on for home. We had a relaxing, rewarding, bonding trip. Our boys (and their parents) got to learn together and see this wonderful country which defines Australia in so many ways.
Total flying time was approximately 14 hours over 8 days, a trip which, in fairness, would have taken three weeks by car if you could get through some of the cut roads in the flood regions.
Craig Hobart
David Jaffray
Last November, on a sunny afternoon with scattered cloud, I turned the key and Warrior IJK spluttered once then burst into life. Unremarkable, unless the last time you did this was 1977.
In my first year out of school, 1971, aiming for a career in flying, I did a PPL at Bankstown and passed CPL theory exams. Then, uncertain of job opportunities, I decided a flying career was not for me and didn't continue. As a university student, finding the dollars to fly enough to stay current was a struggle. For that period, '90 day check' is the most common entry in my logbook. However, eventually, life moved on, other interests took over and flying became a thing of the past. Apparently, on June 13, 1977, I took a Cherokee out to the training area for 35 minutes and that was it for twenty-eight years.Meanwhile, back at the sunny day last year in November, beside me in IJK was instructor John Lowing. In the lead up to the day, I had called CFI Rodney Hyde and explained that I wanted to fly again after a long absence. Whether it was because he could hear the years in my voice I don't know, but he matched me up with John. I hasten to add that I'm not quite as old as John is, but at least when he compared my taxiing to Jack Brabham, I knew who he was talking about.
The first hour went well, mostly. I was relieved when John said he could tell I'd done it before. We flew around in the training area, dodged the scattered cloud, climbed, descended and did some steep turns. But when it came time for a straight-in approach, things went awry. In the 1970s, pilots occasionally requested straight-in approaches but they were almost never approved. You joined on downwind or crosswind and that was that. At this point, John had to take over and bring us home safely.
David Jaffray over the Harbour Bridge I shudder when I recall the next few hours. We flew circuits. Now, the only evidence that I had done it before was that once over the threshold, the muscles took over and I could touch down with some control. Other pilots had said: "It'll be just like getting back on a bike". They meant that my muscles would remember what to do. And they did. But my mind had forgotten the speed, the height, the rpm, the time and the place to do it!
Still lacking polish on circuits, we moved on to revise practice forced landings, precautionary searches and instrument flying. Circuits would improve on the way through.
It took me five navs to get back into the swing of cross-country flying. The first was to Cessnock and the last Victor 1 and Sydney zone. Doing the navs, I realised the shortcomings in my 1970s training when my instructors were happy if I could fly them around without getting lost. I recall having a diversion explained to me once, but never having to actually fly one. I don't know if it's a new syllabus, the rigour of John Lowing's instruction, or both, but after Cessnock, every nav but one, had at least one practice engine failure to handle and a diversion to fly. When John asks to borrow your map, you know you won't be flying the current heading for too much longer. The challenge of the navs has given me a confidence in flying cross-country that I didn't achieve the first time around.
On 18 March 2006, I did a biennial flight review (BFR), and passed. I was current again! I have to say, that the whole refresher course turned out to be far more challenging than I expected it to be, but then twenty-eight years is a long time. The muscles may have remembered, but I'd forgotten how much there is for the head to forget.
How long did it take? All up, 12 hours of general flying and 12 hours of cross-country flying, then the BFR. If you are thinking of doing the same, based on my experience, a rule-of-thumb might be to allow an hour for every year since you last flew.
Was it worth it? Absolutely!
David Jaffray
CONTINUED FROM LAST MONTH...
TUESDAY, MAY 23: We depart Mt Isa for Adels Grove. The terrain is interesting and we find the strip, thanks to Kristin's superior map reading and "feature" interpreting skills. The strip looks thin and sandy, clear at each end, with a low escarpment a mile away. The GPS issues a terrain warning as we turn on to base but we land easily and tie down with the others.
Katherine from the air The bus takes us to the campsite, a big central building with a dining room, bar and a shop near the river. We are in good tents and after a meal we go down to the river. Felix and I hire a canoe - Felix rows for his school so is OK in the canoe. Not so my fat self; I nearly upset the canoe. We paddle and paddle along the pleasant waterway until a gorge with high cliffs and a dangerous looking overhang appears. Felix steers the canoe into the bank and considers going ashore but the bank is too steep. We paddle further and see the falls. A rather low but vigorous flow of water from several directions and a strong current as we get near. We find the landing, tie up the canoe and explore. Back in the canoe Felix wants to get nearer to the falls. The current catches us, and we are pushed into the nearby bank. We try again but are nearly run aground on rocks. We then decide to turn for home. It's easier now with the current pushing us and we make it back quickly. I find it difficult to get out of the canoe after the unaccustomed paddling and using back muscles I didn't know I had. I go for a walk to get a photo of the falls from a high point. Later, we have drinks in the cool of the evening and a pleasant meal, then off to bed.
WEDNESDAY, MAY 24: Our guide Frank, a descendent of one of the early pioneer settlers, takes us to the famed Riversleigh Fossil Fields. We see dingoes on the road and meet up with a group of men and a helicopter mustering hundreds of wild cattle. Very interesting to talk to the boss drover and watch the adroit chopper pilot's mustering skills. The fossil fields are extensive but we only have time to see one site and our guide points out relics of prehistoric animals embedded in limestone rock and gives us an insight into the earliest life forms on earth.
Mataranka, 50NM south of Katherine THURSDAY, MAY 25: We depart Adels Grove for Mataranka Homestead (about 50NM south of Katherine. We track to Boorroloola to refuel where there is a large flock of birds on the runway who won't move so we land as short as possible to avoid running into them. We refuel and set off for Mataranka. Once again Kristin's interpretive skills pick out the strip near a bend in the Roper River. The strip seems to be three colours: sandy, red and green and, as we approach, we notice trees each end and low scrub at the far end. Kristin has to break hard to avoid the low scrub and we taxi back and tie down in some long grass and scrub.
The accommodation is a short walk from the strip and is a big roofed area. The eating and drinking areas are decorated to represent the characters in the iconic outback book "We of the Never Never". A reconstructed house nearby is a replica of the original "Elsey Downs Station" homestead. We have the best Barramundi here - Roper Barra is undoubtedly the best. The management is Swedish and Felix chats to the pretty waitress in Swedish. Kristin also talks to them and we are accorded good service and more Barramundi than we can eat. We explain to our hosts about the airstrip and what can be done to make it more 'user friendly'. We find that the management only took over a few months ago and are recovering from a big flood only weeks ago which caused a lot of damage and left a big crock ensconced behind the bar as the waters receded. Grahame and Helen Smith and Carole joined us here. The evening entertainment is live music and singing and, as the evening progresses, dancing as well. Kristin joins in (what energy she has!)
CONTINUED NEXT MONTH...
Bill Larkin
Bill, age 74, has been flying for 30 years. After being almost a passenger on three Schoies Flyaways he felt that this time he would fly the trip myself but still needed a co-pilot; Kristin filled that position admirably. He hasn't hung up his headset yet - he's going on the Tassie Tour on Boxing Day, and looks forward to seeing everyone in Hobart!
OUR NEW JABIRU VH-LSN IS NOW ON LINE AND AVAILABLE FOR HIRE!
VH-LSN, the Club's new Jabiru J-160 CHECK THIS OUT! The Jabiru is waiting for you. This aircraft has been purpose built for the Club as a state of the art trainer and tourer, and it is now available for both training and private hire.
- All composite construction
- Full glass cockpit with airliner style primary flight display (PFD), electronic engine monitoring system (EMS), moving map GPS
- Dual VHF comms and transponder (OK for all controlled airspace)
- Standby analog instrumentation (if you want to cheat)
- Specially strengthened undercarriage (to cope with flying school challenges)
- Very roomy cockpit (much wider than C152) with a spacious luggage area
- Nimble and responsive performance with a forgiving nature
- Registered in VH general aviation category, with Night VFR approval
- Economical 85HP Jabiru motor sipping about 14 litres per hour
- Performance on par or better than a Cessna 152 (100kts TAS cruise) but 6+ hours endurance (if your bladder can last that long)
- Useful load 233 kg (2 big people with several hours fuel)
- MTOW 540kg (one third lighter than a Cessna 152).
Jabiru J160 85BHP 2200cc engine FOR THE PPL/CPL
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| Private Hire | $125 per hour incl GST plus landing and fuel levy | |
| Dual | $186 per hour incl GST plus landing and fuel levy (less for VETAB) |
VH-LSN, the Club's new Jabiru J-160 Get into our Jabiru J-160! with this special introductory offer to members. Join us in a fun way to become acquainted with the Jabiru in our Jabiru Familiarization and Approval Programme.
THIS INCLUDES
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Spacious seating in Jabiru VH-LSN HOW MUCH?
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** PLEASE NOTE ** As is the case for any of our fleet, approval to hire the aircraft privately depends on the pilot being able to demonstrate the required level of proficiency for safe operations. This may require additional dual instruction to the above, at normal rates.
Wayne Russell
Last month's quiz posed the question "Some ADF receivers have a setting marked 'BFO'. What is the purpose of this setting?"
The 'Buttons' We had 12 correct answers this time (well done, everyone!) The best answered was all the way from the UK, Troy Smith. After all the correct answers went into the hat, Troy's didn't come out. You can blame my XYL, Troy - she picked the winner, student pilot, Howard Elsey.
THIS MONTH'S QUIZ: You sit in the pilots seat of a Warrior. Let your left knee touch the side of the aircraft. Come towards the rear of the aircraft approximately 500mm. There are two buttons on the side of the aircraft, between your waist and your backside. What is the purpose of these buttons?
Correct answers received by Wayne Russell by Friday, 11 August will go into a draw for another 'mystery prize' - winner(s) will be announced in the next Newsletter.
Wayne Russell
Flight Instructor
BEAT FREQUENCY OSCILLATOR - BFO: The quiz in "Wayne's World" last month had me thinking about the BFO option which is standard on most ADF receivers but that most pilots have no idea of its function. Unfortunately Wayne's YF didn't draw my answer out of the hat, so I thought I'd reproduce it here.We know that the direction-finding function of the ADF makes use of the NDB carrier and that audio modulation is used to identify the NDB. So what does an NDB sound like if it is transmitting only the carrier, with no audio? Anyone who has listened to an ADF knows, although he may have paid no attention to it. In between identifications or audio transmissions, the tuned ADF receiver is quiet, in sharp contrast to the noise that comes from an ADF receiver when no NDB is tuned in. The carrier's presence can be recognized when the ADF receiver becomes quiet as the strong carrier covers up the noise. With a weak station we would also hear some noise, and the presence of the carrier would make a slight reduction in the intensity of the noise.
The purpose of the BFO is to have the presence
Ballarat NDB of the carrier produce an audible output from the ADF. With the BFO on with a station is tuned in, a tone will be heard from the ADF audio output, even though the station is transmitting only unmodulated carrier. If the BFO is turned on while the station is transmitting audio, such as the identifier or ATIS, the tone will be heard in addition to the audio. This will make for a jumbled audio output that will most likely be difficult or impossible to understand. The BFO should be off when you want to listen to the audio from a station.
So why would you want to make the carrier audible? One reason is for the identification of some overseas NDBs. To explain this, we must understand how NDBs identify themselves.
The voice identification on many NDBs is obvious, so let's look at the Morse identification. Many stations are identified by the tone heard as coded letters - this tone is a modulation on the NDB carrier. That is, it is just as if someone were at the station, whistling the code into a microphone. NDBs in Australia are identified this way. Some foreign NDBs, however, identify in a different manner. They are able to transmit only carrier, and there is never any modulation on it. They identify themselves by interrupting the carrier (turning the transmitter on and off) in a coded fashion. In order to hear the carrier, one must have the BFO on and the tone will go on and off with the carrier. It would sound very similar to the code identification of a regular Australian NDB, but it is produced in a completely different manner, and the BFO is necessary to hear it. Without the BFO, a clicking or a slight change in background noise might be heard as the station was turned on and off, but it would be very difficult to identify the code.The name Beat Frequency Oscillator comes from the method used to make the carrier audible. A signal that is close to the frequency of the receiver's Intermediate Frequency (IF) is injected into the IF amplifier. This injected signal then mixes with the signal from the ground station that is tuned in. This mixing process causes the carrier signal to become modulated in the receiver. This signal is detected and produces the audio output.
The same effect is often observed when more than one station is being received on a VHF receiver at the same time. There is a 'whistle' mixed in with the two stations; this is caused by the two signals mixing together in the receiver to produce the audio tone, which is the difference in the frequency of the stations.
FEEDBACK AND CONTRIBUTIONS: Well, that's your Newsletter for this month. With help (in the form of contributions) it might be possible to continue to produce a newsletter every month. Don't forget to check the latest news on the Club's website at www.schofields-flying-club.com.au. Contributions, comments, feedback, and suggestions to latrodectus@schofields-flying-club.com.au.
THOUGHT FOR THE MONTH: A helicopter is a collection of rotating parts going round and round and reciprocating parts going up and down - all of them trying to become random in motion. In fact, helicopters can't really fly - they're just so ugly that the earth immediately repels them. (Only kidding, Patrick!)
Latrodectus
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