My V-max has an Eros style turtledeck and canopy installed, locking closed with the stock over center latching system. I have seen several references on here to a secondary "safety catch" to keep the canopy from flying open should it become inadvertently unlatched in flight either by rough air or unintentional operator interference.

does anyone have pics / details of this setup?

Chris

This became a mandatory mod in the UK after a canopy came open, a/c stalled in and fed the pilot's wife (who was walking the dogs on the field) through the rotating prop disc and U/C! She was scalped, one of their dogs was killed but pilot walked away....

No pic at the moment but basically a piece of spring steel with dog leg fold (joggle in UK parlance!) that locks over a bracket. You just have to lift it off and open the canopy at the same time. It doesn't replace the normal mechanism.

My safety catch is of the design used in most UK Minimaxs.

Again no pics handy, but imagine a short peg fitted horizontally somewhere along the fuselage top longeron, just below where the canopy comes down onto it.

Attached to the inside of the coresponding 'longeron' of the canopy structure is a springy plate, extending abt 4 inches below the canopy and abt 1.5 inches wide. In the middle of the plate a vertical slot is cut. The lowest part of the plate is bent a little inward. As the canopy is closed the peg meets the inside of the plate. The plates bent part rides over the peg pushing it inward to the cockpit until the peg drops into the slot in the plate.

To open just pull the plate toward you to clear the peg and raise the canopy.

This system is not foolproof. I am the fool which proves that statement. I once forgot to latch the canopy shut. The canopy lifted on take-off because of the low air pressure above the canopy. It lifted only as far as the slot would let it. Oh bugger. Well, all I need to do is operate the over-centre latch. Instead, I operated the spring plate through habit, and the canopy came fully open just after take-off. I have a permanent slight limp now when I walk.

An advantage (if you are brave) is that the latch can be opened in flight so that the safety plate allows the canopy to rise an inch - then you have some welcome ventilation draught on a really hot day.

I have a second open topped "canopy", it doesn't have the plate arrangement because it naturally wants to close when flying - no low air pressure region above it.

I know of another pilot who got into very serious trouble in the air when his canopy flew open and departed the aircraft. He didn't have the spring-plate device. After getting into some very "unusual attitudes", he landed and was able to go and look for his canopy. He found it in the middle of a crop.

Here's the accident report from my earlier post - makes scary reading!

Information Source: AAIB Field Investigation
The home-built aircraft had been completed by the pilot in 1994and was kept at Ginge Farm airstrip
close to East Ginge, approximatelyhalf a mile to the north of the 'Ridgeway', which is a publicrightof-way and scenic walk on the crest of the Downs.
On the day of the accident the pilot, accompanied by his wife,brother and partner, and two dogs,
arrived at the farm airstripfor the start of an afternoon walk along the 'Ridgeway'. The
pilotremained behind, in order to prepare his aircraft for take off,as the group ascended the hill. He
planned to reposition the aircraftin a large 100 acre field on top of the Downs and to meet up
withhis group for the walk. On their return he would depart the field,fly for some 20 minutes and
return to the farm strip in the valleybelow. The pilot reported that the weather at the time was
finewith visibility in excess of 25 km with a light north-westerlywind of 5 kt, broken cloud above
2,500 feet and a temperatureof approximately 25°C. Having landed in the upper field thepilot
parked his aircraft in some rough grass close to a lineof trees, removed the aircraft keys, closed the
canopy and rejoinedhis family.
When the group returned to the field after their walk the pilotdecided that, as there was now
insufficient time available forthe planned 20 minute flight, he would just take off, climb toa
suitable height and position for a downwind right-hand circuitto land on the farm strip below. His
wife, with the two dogs,remained in the field to watch his departure while his brotherand partner
started to make their way down the hill.
After engine start the pilot manoeuvred the aircraft in a sweeping'S' turn to take off in a north
westerly direction. After takeoff the aircraft was seen to climb sharply and enter a steeplybanked
turn to the right. The pilot reported that as he enteredthe turn the canopy appeared to come
unlocked and he removed hisleft hand from the throttle to hold the canopy closed. As he didso
engine power reduced. The pilot was not aware of the reasonfor the power reduction at the time
although he later surmisedthat engine vibration may have caused the throttle to close. Believingthat
he had an engine failure, he continued to turn right in orderto land back close to his point of
departure. With the tree lineclose by he tightened the turn which resulted in the aircraftstalling,
'flicking' into a level attitude and descending in astalled condition. With the wings level and the
aircraft in ahigh nose attitude there was insufficient time and height forthe pilot to effect a stall
recovery. His only option was to stallstraight ahead. The aircraft hit the ground in a high nose
attitudeand came to rest within a very short distance damaging the mainlanding gear and dislodging
the engine from its mountings. Assoon as it was stationary the pilot switched off the fuel andfully
opened the canopy whereupon he became aware that his wifelying on the ground close to the rear
of the fuselage in a stateof distress. It was only at this time that the pilot realisedthat his wife had
been struck by the aircraft during the landing.
The pilot's wife, who had been watching the manoeuvring aircraft,did not realise until it was too
late that the aircraft was outof control and heading straight for her. The aircraft collidedwith her
and the propeller struck her head as she passed beneaththe fuselage but above the strut connecting
the two main wheels.Although suffering from head and leg injuries she remained conscious.The
dog that she had been holding in her left hand on a lead waskilled in the collision. The pilot was
quickly joined by the twoother members of the group who tended to his injured wife. A
nearbywitness summoned help using a mobile 'phone. The emergency serviceswere alerted and at
1650 hrs the Thames Valley Police helicopter,flying in the vicinity at the time, landed close by the
crashsite. At 1735 hrs, with a paramedic in attendance, the wife wasairlifted from the scene and
arrived at hospital ten minutes later.
Aircraft handling characteristics
A British Microlight Aircraft Association (BMAA) test pilot, familiarwith this type of aircraft, was
consulted on the aircraft's handlingcharacteristics. He stated that the aircraft shows a tendencyto
'flick' level if banked steeply and pulled through the turn,with either high or low power settings.
The rate of 'flick' exceedsthe rate of roll achieved through normal aileron application.Moreover the
aircraft will 'mush' in the stall with no proper'break'. In this condition the nose remains high and the
viewover the front cowling is limited particularly if the engine installationis raised as in the case of
the accident aircraft. Due to thefull span ailerons, the roll control remains effective throughoutthe
stall envelope, though the authority is much reduced due tothe low speed.
Ground impact marks
The aircraft had landed on grass on a heading of 240º(M)on a slight up-slope. Three distinct gouges
in the earth markedthe impact positions of the main wheels and the propeller. Theaircraft had then
bounced nine metres forward, where it had cometo rest. The initial entry angle of the first ground
mark indicatedan angle of 22º below the horizontal. The ground marks showedthat the aircraft had
hit the ground with wings level at a lowforward speed and a high sink rate, compatible with being
in astalled condition. The lightly loaded tail wheel had probablycontacted the ground first, arresting
the descent of the tail.The main energy had been dissipated through the main wheels andtheir
supporting structure.
Aircraft Information
The impact had collapsed the fixed main landing gear, and hadfractured the alloy hub on the left
main wheel. The three propellerblades were still loosely attached to their boss. The tip of oneblade
had detached, and another showed evidence of impact damage;the boss attachment bolts had bent
and released most of the wedgesused to determine the propeller blade angles. All three
glassreinforced plastic (grp) blades showed evidence of rearwards bendingin the form of gel coat
fractures on their forward faces and bucklingon their rear faces.
The engine mounting structure had failed and the engine had rotatedforward through 90º allowing
the nose section to ride overone propeller blade. Apart from this damage to the nose structure,the
fuselage and wing structure were largely devoid of obvioussigns of damage caused by the impact.
One alloy rod in the over-centring canopy locking mechanism wasbent, preventing the mechanism
from locking the canopy shut. Itwas not known whether this damage had been caused by the
impact.
Engine
The engine fitted was a Rotax 503, but it had retained the Mikunifuel pump associated with its
original 447 cc engine. The fuelpump output may have been marginal for the larger engine.
Thecarburettor vent lines were contaminated; blockage of these linescould have prevented air
entering the float chamber and causedloss of power. The fuel filter bowl was contaminated with
finesilt; the fuel pump filter had been cleaned as part of the preparationfor the permit renewal.
The fuel cock was 'OFF', and the throttlewas found in the fully forward position, however, this could
havebeen caused by the movement of the engine off its mountings. Thechoke cable had been
similarly affected and had pulled the innercable out of its soldered housing at the cockpit end.
The nature of the Rotax engine means that the throttle is springloaded to the idle position. To apply
power the carburettor springtension must be overcome. Most builders of the Minimax
incorporatefriction clamping for the throttle, by using friction washersat the pivotal point on the
throttle lever. The accident aircraftwas similarly fitted. There is a tendency, however, for theseto
loose their friction and they regularly need tightening.
Propeller
The relative lack of damage to the propeller, and the lack ofpropeller slash marks on the ground
indicated that the enginehad been running at low RPM. This would be consistent with a
throttlesetting at idle power.
Documentation
The aircraft did not have a current Permit to Fly, but had satisfiedthe technical part of the
application procedure. The engine andaircraft log book details were incomplete, and inaccurate
regardingthe engine and propeller. The aircraft was fitted with a threebladed propeller which had
not been cleared by the Popular FlyingAssociation (PFA) for the aircraft type, although it may
havebeen accepted if the results of a satisfactory airtest had beenpresented to the PFA.

Hello,

Further to Antoni's post above about a safety catch to prevent the canopy from opening.  Please see the photos attached to this post to see what he's on about.

Thanks Bob, That clarifies a lot!

Chris