Centaurus
31st Jul 2017, 13:45
ATSB Report on Jabiru fatal crash after late go-around then stall in landing configuration.
https://www.atsb.gov.au/media/5773325/ao-2016-112-final.pdf
I have only flown about ten hours on LSA and that was in a Texan Club from Penfield, Victoria during the last 4 years. .
When I flew the Texan Club I was caught by surprise that on touch and go landings, considerable rudder deflection was needed when full throttle was applied to keep the aircraft straight on the grass airstrip; and this was in nil wind. The lower the airspeed the more was corrective rudder required.
The ATSB report quoted an instructor as saying that when close to the runway, the Jabiru, like any high wing aircraft of a similar design, had a tendency to pitch-up when full flap and throttle were applied. Forward pressure on the control stick would have to be used to counteract this tendency. This applies to most types of aircraft including aircraft like the Cessna 152 and its ilk.
It is apparent that the Jabiru bounced several times before the pilot made an attempt to go-around. By then, the airspeed would be on the stall when he applied power to go-around. With full power, full flap down and airspeed bordering on the stall, the amount of rudder to keep wings level to counteract torque would be nearly full rudder. That is probably why the aircraft yawed into an angle of bank of 30 degrees because the pilot either had full rudder and was still unable to stop the yaw – or he had insufficient rudder in the first place. The result was predictable.
While in flying schools it is common practice to conduct go-arounds as part of circuit training, these are normally conducted on short final where ample airspeed is still available. From personal observation, few instructors teach students the correct recovery technique from a bounce at low airspeed - including how to cushion a bounce with a trickle of power and re-land straight ahead within the remaining airstrip length. Instead students are advised “when in doubt always go-around”
This sort of instructor exhortation, especially before a student does his first solo, has been thus so since flying first began. So students are drilled that go-arounds in the landing configuration regardless of airspeed is generally safer than recovery from a bounce or series of bounces by landing straight ahead. The short answer is that students should be competent at both sequences; certainly before first solo.
However, as this accident has proven, the result may have been different if the pilot had abandoned any thought of a go-around at such a late time, but instead applied sufficient power to cushion any bounce and re-landed ahead.
A late go-around after the flare or after touch down, brings with it the danger of student mis-handling due to the combination of full flap, high nose attitude, rapidly reducing airspeed, failure to prevent yaw at a high angle of attack and torque effect. All leading to the possibility of an incipient spin. It applies to a Jabiru more than (say) a C152 because of the amount of strong rudder pedal deflection needed to prevent yaw at high power in an LSA.
It could be argued that application of some power to cushion a bounce with the intention of re-landing further down the available landing length, introduces the added risk of an over-run if the student mis-judges the remaining landing length available. While that is true, it could also be argued it is safer that risking an incipient stall/spin which happened in the Jabiru fatal accident. In any case, the student should not be certified safe for solo until he has proved to be competent at not only low speed go-arounds but also bounced landing recovery by re-landing straight ahead.
During my time as a RAAF QFI teaching ab-initio students in the days of Tiger Moths and Wirraways, it was mandatory to teach bounce recovery or high hold-off situations, where a re-landing ahead could be safely attained. On graduation pilots could be posted to fly Mustangs or Sea Furies where a slow speed delayed go-around had the potential of being quite dangerous.. These aircraft with their powerful engines, could torque roll caused by an uncontrollable yaw with rapid application of power.
Flying school ab-initio training syllabus should require proven competency at the technique of re-landing straight ahead, where applicable. The potential dangers of very low airspeed go-arounds in the landing configuration should also be included in the syllabus, if it isn't already.
https://www.atsb.gov.au/media/5773325/ao-2016-112-final.pdf
I have only flown about ten hours on LSA and that was in a Texan Club from Penfield, Victoria during the last 4 years. .
When I flew the Texan Club I was caught by surprise that on touch and go landings, considerable rudder deflection was needed when full throttle was applied to keep the aircraft straight on the grass airstrip; and this was in nil wind. The lower the airspeed the more was corrective rudder required.
The ATSB report quoted an instructor as saying that when close to the runway, the Jabiru, like any high wing aircraft of a similar design, had a tendency to pitch-up when full flap and throttle were applied. Forward pressure on the control stick would have to be used to counteract this tendency. This applies to most types of aircraft including aircraft like the Cessna 152 and its ilk.
It is apparent that the Jabiru bounced several times before the pilot made an attempt to go-around. By then, the airspeed would be on the stall when he applied power to go-around. With full power, full flap down and airspeed bordering on the stall, the amount of rudder to keep wings level to counteract torque would be nearly full rudder. That is probably why the aircraft yawed into an angle of bank of 30 degrees because the pilot either had full rudder and was still unable to stop the yaw – or he had insufficient rudder in the first place. The result was predictable.
While in flying schools it is common practice to conduct go-arounds as part of circuit training, these are normally conducted on short final where ample airspeed is still available. From personal observation, few instructors teach students the correct recovery technique from a bounce at low airspeed - including how to cushion a bounce with a trickle of power and re-land straight ahead within the remaining airstrip length. Instead students are advised “when in doubt always go-around”
This sort of instructor exhortation, especially before a student does his first solo, has been thus so since flying first began. So students are drilled that go-arounds in the landing configuration regardless of airspeed is generally safer than recovery from a bounce or series of bounces by landing straight ahead. The short answer is that students should be competent at both sequences; certainly before first solo.
However, as this accident has proven, the result may have been different if the pilot had abandoned any thought of a go-around at such a late time, but instead applied sufficient power to cushion any bounce and re-landed ahead.
A late go-around after the flare or after touch down, brings with it the danger of student mis-handling due to the combination of full flap, high nose attitude, rapidly reducing airspeed, failure to prevent yaw at a high angle of attack and torque effect. All leading to the possibility of an incipient spin. It applies to a Jabiru more than (say) a C152 because of the amount of strong rudder pedal deflection needed to prevent yaw at high power in an LSA.
It could be argued that application of some power to cushion a bounce with the intention of re-landing further down the available landing length, introduces the added risk of an over-run if the student mis-judges the remaining landing length available. While that is true, it could also be argued it is safer that risking an incipient stall/spin which happened in the Jabiru fatal accident. In any case, the student should not be certified safe for solo until he has proved to be competent at not only low speed go-arounds but also bounced landing recovery by re-landing straight ahead.
During my time as a RAAF QFI teaching ab-initio students in the days of Tiger Moths and Wirraways, it was mandatory to teach bounce recovery or high hold-off situations, where a re-landing ahead could be safely attained. On graduation pilots could be posted to fly Mustangs or Sea Furies where a slow speed delayed go-around had the potential of being quite dangerous.. These aircraft with their powerful engines, could torque roll caused by an uncontrollable yaw with rapid application of power.
Flying school ab-initio training syllabus should require proven competency at the technique of re-landing straight ahead, where applicable. The potential dangers of very low airspeed go-arounds in the landing configuration should also be included in the syllabus, if it isn't already.