AEROPLANES
15 Dec
Brugger Colibri
MB2: G-BUDW: Northfield
Farm Strip, Spilsby, Lincs
The owner kept his single seat
aircraft at a small farm airstrip near Mavis Enderby in Lincolnshire. In the
months leading up to the accident it was reported that the engine had been running roughly with loss of power in flight. In April 2019, he had an engine failure
and landed in a field. He was able to fix the problem and took off
again 40 minutes later. It was reported that he had aborted several flights in recent months and
returned to the airfield due to engine problems. The owner had tried several
solutions.
The aircraft had been built in
1992 and the original owner and builder flew the aircraft until 2000 when the
aircraft was damaged during a forced landing. The airframe was repaired,
and the Volkswagen engine was rebuilt with its capacity increased from 1600 cc
to 1834 cc. The current owner purchased the aircraft in 2007 and flew it
regularly. He undertook the maintenance of the aircraft himself, but no
evidence of a maintenance programme was found. The aircraft’s Annual Inspection was carried out by a local LAA inspector, as
required to maintain the Permit to Fly. Since the engine had been rebuilt, 605
hours of running time had been logged.
The aircraft was seen taking
off and turning to the north. Two witnesses reported hearing the engine running
roughly. The accident site was discovered approximately one hour later, the
pilot had been killed. The
most likely scenario is that after the turn to the north the pilot tried to fly
a circuit to the north of the airfield in an attempt to land back on the
runway. The impact marks suggest the aircraft was turning to align with the
runway when it struck the ground.
The investigation found that the engine was in poor condition with multiple defects
which could have caused the loss of engine power and rough running. The most
significant of these were the crack in the cylinder head, the split in inlet
manifold joint and deposits on the valve seats. The crack in the head of
cylinder 2 would have resulted in a reduction in compression and engine power.
The split in the manifold would allow air into the manifold, weakening the
mixture and causing the engine to run hot. The deposits on the valves were most
likely a mixture of carbon and oil and not untypical for an engine of this age.
In cylinders 1 and 2 it was noted that some of the deposit had flaked off the
head and there was evidence that these flakes had been caught and crushed in
the valve seats. This would have prevented the valves from sealing, resulting
in low compression and loss of engine power, only cylinder 4 sealed effectively. The weather conditions
on the day were also conducive to carburettor icing and following the long taxi
over wet grass, this may have further reduced engine power.
The pilot had made several
changes to the aircraft fuel system whilst attempting to resolve the engine problem. There was no
evidence that these changes had been inspected by a LAA inspector or that they
had been discussed with, or approved by, LAA Engineering. Whilst there is no
evidence that these contributed to the accident, it is important that
owners/pilots should follow the correct inspection and approval process when
making changes to the aircraft configuration. The LAA provide guidance on this
process and LAA Engineering should be contacted if there is any doubt on
whether approval is required. The 55 year old pilot had flown 1,300 hours
with 221 on type. (AAIB Bulletin 11/2020 & Addendum in 1/2021).
25 Nov
Cessna 172S: G-CBXJ: Nr Puffin Island, Anglesey, Wales
AAIB Summary and Conclusions:
The aircraft was on a local flight when it descended into the sea, killing the pilot. No definitive cause for the accident could be found. There was no evidence of a structural failure leading to the accident and a trial to replicate the final flight profile discounted a full or partial engine failure. The trial concluded that it was likely the aircraft required an input on the controls in order to enter and maintain the recorded final descent path. The pilot had recently been unwell but there was no evidence of medical incapacitation, although this could not be dismissed as a possible cause.
It was concluded that it was not been possible to identify a definitive cause of the accident. Whilst only a remote visual examination of the aircraft was possible, there was no indication of structural failure and the flight trial conducted indicated an engine failure had not occurred. The stability of the aircraft and evidence from the flight trial points to the need for an input on the controls, if only slight, to both enter and maintain a descent along a nearly constant track, as well as turning the aircraft left and then right towards the end of the descent. There was no evidence of medical incapacitation of the pilot, however, his recent illness and the fact that causes of incapacitation are not always evident means that this cannot be excluded. The 79 year old pilot had flown in excess of 2,200 hrs, hours on type unknown. (AAIB Bulletin 12/20).
25 August
Piper PA28-RT201 Arrow !V: G-BVDH: Simplon Mountains
The aircraft took off at about 09:00 from Lausanne La
Blécherette Airport bound for Italy when about 1½ hours later it
impacted the Simplon Mountain, Valais Switzerland at about 6,100 ft killing all
three occupants which included a baby. (ASN)
24 August
Pitts S-2A
The aircraft was engaged on an
aerobatic training sortie to prepare the student to compete in aerobatic
competitions. The accident occurred on his third flight with the
student in the rear
cockpit. It is
believed that upset recovery training and recovery from inadvertent spin entry
would have been likely exercises. The aircraft took off from White Waltham
Airfield at approximately 12.55 hrs. Eyewitnesses over one mile from the
accident site to the North of Henley on Thames recalled last seeing the aircraft in a spin which persisted
for several turns and the aircraft was still spinning when they lost sight of it before it struck the
ground killing both occupants. The commander was an aerobatic and Class
Rating Examiner and an Unlimited Category
competition aerobatic pilot. The
student held an aerobatic rating which requires a minimum of 5 hours or 20
flights and includes spin training and had flown 197 hours with 1 hr 25 mins on
type.
The accident site was approx 500 ft amsl and underneath Class A airspace with a base of 3,000 ft amsl. From 3,000 ft agl, with 500 ft needed to arrest rotation and 500 ft to level, spin recovery would have needed to be initiated within 17 seconds to just avoid contacting the ground. The aircraft was spinning in a steep nose-down attitude at impact.
The post-mortem revealed the 35 year old commander had a significant cardiac condition. While there were no indications of a previous heart attack, there was significant narrowing of a cardiac artery the level of which could have placed the commander at risk of sudden death due to cardiac dysrhythmia. Most cases of such disease in young people are generally only identified at post-mortem with no history of previous symptoms and is particularly rare in those under 40. The commander had shown no history of illness and it is unlikely the condition would have been revealed by an ECG unless a significant physiological burden was applied at the time, this is only required for pilots over 65 for a Class 1 aviation medical. It is possible that the commander could have suffered a significant alteration of cardiac output, sufficient to prevent further control of the aircraft and it would be likely that the commander would have collapsed with little or no warning. It was thought unlikely that the controls would have been impeded preventing recovery action by the student, although a number of factors could have reduced his ability in the limited time available.
The design of the Pitts Special does not have adjustable rudder pedals, and devices have been produced which, when installed would effectively move the rudder pedals aft enabling shorter pilots to achieve full rudder deflection. The alternative to moving the rudder pedals aft would be move the pilot forward with a cushion as the seat positions are fixed, which could compromise the aft movement of the control column against the pilot’s torso. The fitting of such devices should be an EASA approved modification so that their operation and effects can be tested and documented. The investigation was unable to locate any approval for a modification to fit these devices. It was noted during a maintenance check that the devices, which were fitted at the time, allowed for a variety of settings and, in the most extreme configuration, restricted rudder movement by 10° (33% of the rudder travel). Anecdotal evidence suggests that the devices had been used on many previous occasions without any adverse effects being reported. No records were kept detailing their installation or removal.
The aircraft departed with fuel
intended to ensure that the aircraft was within its C of G envelope. As
each of the operator’s instructors had an idea of the limitations because of
their own weight, it was not usual for them to calculate the exact C of G prior
to each flight. The operator had created a spreadsheet to automate the C of G
calculations, which calculated the mass and balance for a range of fuel loads. Figures obtained from the
commander’s computer showed a calculation with incorrect weights for both of the pilots and the aircraft which would have misled the
commander into thinking that the aircraft was within its flight envelope for
the planned sortie. Using
the accurate weights, the aircraft was overloaded for both the Aerobatic and Utility flight envelopes with the C of G further aft than both the published limit. The aircraft manufacturer did not
consider that the overloading would have prevented the aircraft from recovering from a spin but would have
reduced the effectiveness of the rudder and elevator and extended the time required for
recovery. The
operator has taken steps which included the provision of scales so pilots can weigh themselves as they
had found large
discrepancies between given and actual weights among its pilots and no longer
accepts assumed or estimated weights. The Commander had flown 710 hours with about 172 on
type. (AAIB Bulletin 2/2021}.
21 July
DH82A Tiger Moth: N54556: Private Strip near Hythe, Kent
AAIB Synopsis:
The owner of the aircraft and
his passenger, who was a professional pilot, were to carry out a flight to
familiarise the passenger with the Tiger Moth. The owner occupied the front
cockpit with the passenger in the rear cockpit, from which the aircraft is
flown when solo. They completed a first sortie, which comprised general
handling and circuits and was followed by a short break. They agreed to do some
more circuits with the passenger flying the aircraft. After the first landing, the owner took
control and performed a rolling takeoff and made an early right turn, estimated
by the passenger to be at about 20-30 ft agl. The passenger noticed that the
aircraft was becoming increasingly cross-controlled with full right rudder and
left control stick, which resulted in the aircraft rolling into a steeply
banked turn to the right and striking the surface of a crop field in a steep
nose down attitude. The pilot, in the front cockpit, was fatally injured and the
passenger was seriously injured but able to release himself from the wreckage
and drag himself clear. The
accident occurred because the increasing amount of right rudder was not reduced
and left roll control stick reached the limit of its travel causing the
aircraft to enter a descending, steepening turn to the right, and possibly to
enter an incipient spin, before striking the ground. The reason for the loss of
control was not determined, but the possibility that the pilot became
incapacitated could not be excluded. The 51 year old pilot had flown 523
hrs with 77 on type. (AAIB Bulletin 8/2020)
13 June
Bristell NG5 Speed
Wing: G-OJCS: Belan, Nr Moone,
Co Kildare, Ireland
The aircraft with two on board took off from Kildare
aerodrome at approx 19.30 on a local flight. When it failed to return, a
search was carried out and the wreckage was located by the Irish SAR helicopter
at about 04.30 the following day. Both occupants had died in the
crash. (Source ASN)
16 May
Diamond DA62: G-MDME: 3 nm south of Dubai International Airport, UAE
On 16 May 2019 at 18:08 local time, the twin engined aircraft, was
carrying out aerodrome ground lighting calibration checks at Dubai
International Airport as art of the southern runway refurbishment
project. Onboard were two flight crewmembers, a calibration engineer and
an observer. The ground lighting check required the aircraft to fly a number of
VFR approaches to, and low passes over, runway 30L. Prior to departure, the
flight crew met air traffic control and airport representatives to discuss the
calibration flights including that ATC would communicate with the DA62 on a
separate frequency. At 18:08 the aircraft took off from runway 30R
to fly its first calibration approach to runway 30L flying a total of nine
circuits performing different aerodrome lighting checks. At 19:29,
the aircraft entered the final approach to runway 30L for the tenth approach,
following a Thai Airways Airbus A350-900 which was flying the approach to the
parallel runway 30R. The Airbus was approximately 3.7 nautical miles (nm) ahead
of the DA62.
When the DA62 levelled
off after turning onto final at an altitude of approximately 1,100 feet (ft)
and at an airspeed of approximately 130 knots (kt), it rolled slightly but was
recovered after nine seconds. Seven seconds later, the aircraft abruptly rolled
to the left until it became inverted and it then entered a steep dive. The
aircraft impacted the ground approximately 3.5 nm from the runway 30L
threshold. The aircraft was destroyed by fire. Evidence
at the accident site indicated that the aircraft impacted the ground at an
elevation of approximately 130 ft while travelling at high speed in the
direction opposite to the direction of flight, on a heading of approximately
100 degrees.
In their final report AAIS confirmed that the accident was due to an in-flight
loss of control during the approach to runway 30L caused by an encounter with
wake vortices generated by a preceding Airbus A350-900 aircraft, which was
approximately 3.7 nm and 90 seconds ahead on the approach to runway
30R. Contributory factors included the pilot’s decision to reduce
the self-separation from preceding air traffic during approaches to runway 30R,
and wind conditions in which the wake vortices from the approach path to runway
30R drifted across into the approach path to runway 30L. The Operator
lacked an effective safety management system, which prevented the
identification of operational hazards during calibration flights, in particular
calibration flights carried out at airports during times when more than one
runway was in operation. The 52 year old pilot had flown a total of 3,441
hrs with 645 on type.
(UAE Preliminary Report AIFN/0007/2019 via
ASN)
3
February
Luton LA4A Minor: G-AWMN: Nr Belchamp
Walter, Essex
The pilot was
conducting a test flight in the VW engined single seat homebuild to renew the
aircraft’s Permit to Fly. Whilst climbing away from the 500 metre strip at
Waits farm, the aircraft was observed to bank to the right and then descend
steeply to the ground killing the pilot. It was not possible to
definitively determine the cause of the accident. It is possible that the
engine stopped producing power due to carburettor icing which led to a stall
from which the aircraft was not able to recover. The investigation also
identified that, despite wire locking being present, the barrel from an aileron
flight control turnbuckle was missing, but it could not be determined if this
had been missing prior to the accident.
(AAIB Bulletin 11/2019).
21
January
Piper PA-46 310P Malibu: N264DB*: Nr Alderney, Channel Islands
The US Registered single piston engined aircraft has gone
missing near Alderney after contact was lost while en-route from Nantes, France
to Cardiff with one passenger and the pilot on board. (Source ASN). * Reportedly
9 January
Piper PA28R-201 Arrow
III: G-OARI : Mount Ernio, Errazil, Spain
Summary of event: The aircraft had taken off at 08:30 UTC
(09:30 local time in Spain) from the municipal aerodrome of Cascais, Portugal,
en route to the airport of San Sebastian. The flight was taking place under visual flight rules
(VFR). At around
12:00 UTC (13:00 local time),
the aircraft was near Bilbao
Airport. The crew contacted
the approach controller at this airport via radio, and at 12:10 UTC, the
controller transferred the
aircraft to the San Sebastian control tower. Minutes later, the radar signal was
lost. The crew never
made radio contact with the San Sebastian
control tower. A
search for the aircraft was initiated, and the wreckage was found at 3,363 ft on the south slope of Mount
Ernio, very close to the summit. Both occupants were killed and the
aircraft was destroyed. The
investigation has determined that the accident resulted from the decision to
continue flying through an
area where the meteorological conditions were below the minimums required for flights being conducted
under visual flight rules (VFR). Improper
flight planning is deemed to have contributed to the accident.
The 62 year old pilot held an EASA CPL with total hours 3,050. The 67 year old passenger also had an EASA CPL with 6,446 hours and 525
hrs on type. (Spanish Authority Report A-002/2019)
MICROLIGHTS
24 July
Evector EV-97 Eurostar: G-SJES: Nr Pre-la-Font, Larche, France
The Eurostar microlight was part of a group of six aircraft
and had departed from Barcelonnette – Saint – Pons, 3,714 ft amsl. The
Eurostar crashed at an altitude of approx 9,100 ft in the French Alps near the
Italian border, killing the two occupants. Another of the group force
landed and was unharmed; the two events are not thought to be linked.
(Source: ASN & media).
28 June
Pegasus
XL-R: - Nr Rathcash, Co Kilkenny, Ireland
The aircraft crashed after colliding with power cables
while making a local flight from a private strip near the pilot’s home killing
the one person on board. (Source: Media etc)
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