Mon Apr 23, 2012 12:51 pm
#1058763
The Price of Trinkets
David Phillips tells the tale of four friends, shopping for aviation goodies at a trade show, but they get more than they bargain for...
The day had been a success. Pilot X and his three flying compatriots had taken in a well organised and interesting aircraft trade show in the Home Counties. They had left their base early that morning having filled the tanks in the club’s new G1000-equipped C172. A check of the weather indicated a stationary high-pressure system holding to the right of their planned, southbound track with optimistic TAFs. The aircraft had performed well and completed the 250nm trip from Ireland, including the significant sea crossing, in precisely two hours. Throughout the flight, the pilots spent much of the time finding their way around the navigation features of the G1000 MFD.
Met by a fuel bowser on landing, Pilot X made a quick mental calculation and arranged for 50lt of expensive avgas to be added to the tanks. At this, he rushed off and joined his three friends who were already flexing their credit cards with enthusiastic anticipation.
Some six hours later the foursome returned to their aircraft, complete with various aviation trinkets that would undoubtedly make them far better pilots. Pilot X was looking forward to being in command on the return leg, especially since he now had a brand new ANR headset to try.
The four pilots completed a quick walkround, threw their purchases into the baggage compartment, strapped themselves in and started up. While taxying, Pilot X noted that the fuel gauges appeared to indicate less than he expected at just under 15usg a side, but he was sure they would be OK. They had departed this morning with about 170lt of fuel, flown for two hours and he had arranged a 50lt top-up. By his reckoning they must still have about 150lt for a trip that was only going to take two hours. Furthermore, he suspected that a rather tail-heavy attitude meant that the fuel gauges were giving an overly pessimistic reading.
Heavy beast
After a short delay Pilot X was cleared to depart and it was only during the take-off roll that he recognized the degraded performance of the aircraft. He was already aware that the new ‘glass’ C172 was a heavier beast than the more traditional models but he was genuinely surprised at the slow climb rate. Nevertheless, full throttle and a cruise climb of 90kt gave him a climb rate of 500fpm and an average groundspeed of 70kt. After about 15 minutes he levelled the aircraft at 6,500ft and allowed the aircraft to accelerate before finally retarding the throttle and changing frequency to the next ATC unit. ATC was busy and it took some time for Pilot X to get his call in before he finally had time to relax.
Switching on the autopilot and linking it to the GPS flight plan, Pilot X finally joined the animated conversation that was ensuing about the merits of high-wing over low-wing. After about half-an-hour, he completed a FREDA check and noted that the fuel gauges indicated 10usg each. He also mentally chastised himself for not leaning the engine after he had levelled off; he gave the mixture plunger a couple of anticlockwise turns. He again dismissed the low gauge reading as an anomaly due to the rearwards C of G but quietly ran through the day’s fuel calculation. No, he must be right.
Meanwhile the conversation had turned to the aircraft’s performance and ETA. It looked as if the homeward trip was going to take somewhat longer than the morning’s outbound and the pilots discussed the frosty reception they would all receive from their respective spouses. The GPS indicated they still had 160nm to go and just less than two hours flight time. Inevitably, the conversation focused on fuel and the continued inaccuracy of the GA fuel gauges, even on the most modern aircraft.
The pilots each revisited the figures given
by Pilot X and they all agreed that things were fine. Eventually, the most experienced pilot
broke the silence by suggesting that they consider their options in another 30 minutes. Pilot X accepted these wise words and continued towards destination.
Radio silence
Approaching the coast, Pilot X completed his coasting-out checks and recommenced the discussion about fuel. The gauges seemed to have settled around 10usg a side and the quorum decided to press on, there being only 85nm to go. After all, landing at the nearest GA airfield that was 15nm behind them would cost them more money and at least an hour. Some 10 minutes later, the G1000 PFD annunciator panel lit up with a ‘Low Fuel L’ indication. This was accompanied by an incessantly loud chiming noise that took Pilot X some time to silence. Not long afterwards, the chiming returned with an additional ‘Low Fuel R’ annunciation. Pilot X asked for the aircraft flight manual to be passed forward while he juggled with his ANR volume settings… only to be told that the manual was lost underneath a pile of trinkets in the baggage compartment.
By now there were no options − they had to continue towards their home airfield. The next 45 minutes were tense with each pilot continuously revisiting the fuel calculation. As the coast finally appeared, the friends started to relax but Pilot X chose to keep the aircraft high in case the engine started to cough.
Tuning in to the airfield’s frequency, Pilot X wasn’t surprised when he didn’t get a response at this time of the evening. He positioned the aircraft on a long final, completed his checks and reconfigured the aircraft for landing. At about 200ft he looked through the rapidly forming mist and could just make out the club’s Tiger Moth lining up at the far end of the runway. Aware that the old biplane didn’t have a radio, he was still surprised when the aircraft commenced a take-off roll. Pilot X had no option but to select full power, raise the drag flap and, conscious of his parlous fuel state, he commenced a climbing left turn with the intent of completing a tight, low-level circuit. For the umpteenth time the low fuel annunciator started to chime, together with a barely discernable background buzzing.
At 300ft he increased aileron input in order to keep the turn going, while noting that he still had two stages of flap. He quickly reached for the flap switch and raised the last two stages in one go. Some 10 minutes later the local fire brigade arrived at a smoking pile of twisted metal having been alerted by a dog walker.
Questions
1 Fuel planning is obviously an issue. How could a thorough knowledge of the G1000 system have helped?
2 The aircraft’s Flight Manual has some helpful information regarding performance and fuel burn. How relevant would that information have been in this circumstance?
3 What is the most likely cause of the crash?
David Phillips tells the tale of four friends, shopping for aviation goodies at a trade show, but they get more than they bargain for...
The day had been a success. Pilot X and his three flying compatriots had taken in a well organised and interesting aircraft trade show in the Home Counties. They had left their base early that morning having filled the tanks in the club’s new G1000-equipped C172. A check of the weather indicated a stationary high-pressure system holding to the right of their planned, southbound track with optimistic TAFs. The aircraft had performed well and completed the 250nm trip from Ireland, including the significant sea crossing, in precisely two hours. Throughout the flight, the pilots spent much of the time finding their way around the navigation features of the G1000 MFD.
Met by a fuel bowser on landing, Pilot X made a quick mental calculation and arranged for 50lt of expensive avgas to be added to the tanks. At this, he rushed off and joined his three friends who were already flexing their credit cards with enthusiastic anticipation.
Some six hours later the foursome returned to their aircraft, complete with various aviation trinkets that would undoubtedly make them far better pilots. Pilot X was looking forward to being in command on the return leg, especially since he now had a brand new ANR headset to try.
The four pilots completed a quick walkround, threw their purchases into the baggage compartment, strapped themselves in and started up. While taxying, Pilot X noted that the fuel gauges appeared to indicate less than he expected at just under 15usg a side, but he was sure they would be OK. They had departed this morning with about 170lt of fuel, flown for two hours and he had arranged a 50lt top-up. By his reckoning they must still have about 150lt for a trip that was only going to take two hours. Furthermore, he suspected that a rather tail-heavy attitude meant that the fuel gauges were giving an overly pessimistic reading.
Heavy beast
After a short delay Pilot X was cleared to depart and it was only during the take-off roll that he recognized the degraded performance of the aircraft. He was already aware that the new ‘glass’ C172 was a heavier beast than the more traditional models but he was genuinely surprised at the slow climb rate. Nevertheless, full throttle and a cruise climb of 90kt gave him a climb rate of 500fpm and an average groundspeed of 70kt. After about 15 minutes he levelled the aircraft at 6,500ft and allowed the aircraft to accelerate before finally retarding the throttle and changing frequency to the next ATC unit. ATC was busy and it took some time for Pilot X to get his call in before he finally had time to relax.
Switching on the autopilot and linking it to the GPS flight plan, Pilot X finally joined the animated conversation that was ensuing about the merits of high-wing over low-wing. After about half-an-hour, he completed a FREDA check and noted that the fuel gauges indicated 10usg each. He also mentally chastised himself for not leaning the engine after he had levelled off; he gave the mixture plunger a couple of anticlockwise turns. He again dismissed the low gauge reading as an anomaly due to the rearwards C of G but quietly ran through the day’s fuel calculation. No, he must be right.
Meanwhile the conversation had turned to the aircraft’s performance and ETA. It looked as if the homeward trip was going to take somewhat longer than the morning’s outbound and the pilots discussed the frosty reception they would all receive from their respective spouses. The GPS indicated they still had 160nm to go and just less than two hours flight time. Inevitably, the conversation focused on fuel and the continued inaccuracy of the GA fuel gauges, even on the most modern aircraft.
The pilots each revisited the figures given
by Pilot X and they all agreed that things were fine. Eventually, the most experienced pilot
broke the silence by suggesting that they consider their options in another 30 minutes. Pilot X accepted these wise words and continued towards destination.
Radio silence
Approaching the coast, Pilot X completed his coasting-out checks and recommenced the discussion about fuel. The gauges seemed to have settled around 10usg a side and the quorum decided to press on, there being only 85nm to go. After all, landing at the nearest GA airfield that was 15nm behind them would cost them more money and at least an hour. Some 10 minutes later, the G1000 PFD annunciator panel lit up with a ‘Low Fuel L’ indication. This was accompanied by an incessantly loud chiming noise that took Pilot X some time to silence. Not long afterwards, the chiming returned with an additional ‘Low Fuel R’ annunciation. Pilot X asked for the aircraft flight manual to be passed forward while he juggled with his ANR volume settings… only to be told that the manual was lost underneath a pile of trinkets in the baggage compartment.
By now there were no options − they had to continue towards their home airfield. The next 45 minutes were tense with each pilot continuously revisiting the fuel calculation. As the coast finally appeared, the friends started to relax but Pilot X chose to keep the aircraft high in case the engine started to cough.
Tuning in to the airfield’s frequency, Pilot X wasn’t surprised when he didn’t get a response at this time of the evening. He positioned the aircraft on a long final, completed his checks and reconfigured the aircraft for landing. At about 200ft he looked through the rapidly forming mist and could just make out the club’s Tiger Moth lining up at the far end of the runway. Aware that the old biplane didn’t have a radio, he was still surprised when the aircraft commenced a take-off roll. Pilot X had no option but to select full power, raise the drag flap and, conscious of his parlous fuel state, he commenced a climbing left turn with the intent of completing a tight, low-level circuit. For the umpteenth time the low fuel annunciator started to chime, together with a barely discernable background buzzing.
At 300ft he increased aileron input in order to keep the turn going, while noting that he still had two stages of flap. He quickly reached for the flap switch and raised the last two stages in one go. Some 10 minutes later the local fire brigade arrived at a smoking pile of twisted metal having been alerted by a dog walker.
Questions
1 Fuel planning is obviously an issue. How could a thorough knowledge of the G1000 system have helped?
2 The aircraft’s Flight Manual has some helpful information regarding performance and fuel burn. How relevant would that information have been in this circumstance?
3 What is the most likely cause of the crash?