Post by RobinK on Jan 10, 2007 22:24:36 GMT 12
Go back in time to Sunday 25 October 1959. Go back in space to
Wellington's new pride and joy, the virgin runway fortified at each
end against the sea at Rongotai. Go back in events to the air show
staged to mark the opening thereof.
The show was supposed to have been on the Saturday, but Wellington's
weather was in one of its more sullen tempers on that day. The Sunday
dawned better, but not much. No rain or significant cloud, but a very
strong, very gusty nor'westerly gale swinging twenty degrees misaligned
with the runway.
Sunderland flying-boat NZ4113 was charged with a flypast along the
runway to open the show, thence to patrol Cook Strait as
search-and-rescue picket for the rest of the afternoon (inelegantly,
the callsign assigned for the latter purpose was Duckbutt).
My log book reads copilot and, with tactful understatement, records the
manoeuvre as "Touch and Go, Rongotai". The planing hull was breached
in the process. Having become a casualty itself, the aircraft was
obliged to abandon the duckbutt duty in favour of a duckscuttle back
home to Hobsonville.
But before turning to the detail, let me mention an aircraft
that followed us in the programme, a Royal Air Force Vulcan,
tail number XH498. On approach from the south in the tumultuous wind
this aircraft hit the lip of the runway where it falls away into the
sea. One undercarriage leg broke at its root. Though it remained
attached to the aircraft it was free to flap in the breeze - and did.
Fuel lines were ruptured, releasing turbine kerosene to spray
everywhere as the aircraft climbed away. The hapless machine landed at
Ohakea. As expected the damaged leg collapsed during the runout. The
aircraft slewed off the runway on one wheel and the other wingtip,
ploughing up the turf before coming safely to rest. It was repaired at
Ohakea over the next several months, and eventually was flown back to
Britain.
Some show. Some opening. Double trouble.
As the Sunderland sullied the spotless new seal, the sensation from the
cockpit was just a brief couple of mild bumps - rather like a car
negotiating a double speed hump. From the lower deck, however, the
sandpapering noises were louder, more prolonged, and much more
alarming.
The hole was a couple of feet long or thereabouts and about half that
in width. It was big enough to be a worry, shaped like an isosceles
triangle with the pointy end forward. Trapped bilge water sprayed out.
The lowest point of the keel, right at the "step" in the planing
surface, had been ground away. The void was at a junction of several
compound curves in the frames and aircraft skin, and was both too large
and too irregular to plug satisfactorily in the air. (It was also a
bitch to repair later.)
As it happened, the aircraft was rigged for a return passenger run to
the Chathams. At the time, these flights plied about once a month
between Evans Bay and the Te Whanga Lagoon by direction of the
Government; the Member for Lyttelton (which included the Chathams) was
the burly, bluff and highly engaging Norman Kirk. For students of the
history of the New Zealand coastal shipping trade, these flights were
conducted under charter to the then famed Holm Shipping Company.
The substantial land airfield that's now near Waitangi came later.
Meantime the Sunderlands provided an air bridge. (As an aside, a
couple of weeks or so after the events related here we lost a
Sunderland in the lagoon. Whilst taxying where it was thought to be
safe on the line of the lead-in markers, there was an argument with a
submerged and uncharted rock. The rock won. There were no casualties
but the aircraft was kaput; sunk; gone to Davy Jones.)
The significance of the Chathams rig in the context of the runway
touchdown was that the wardroom and another compartment further aft
were converted for passengers. Ordinary airliner seats were installed.
Needs must; their squabs were put to a use their designer could never
have intended nor even envisaged. They were stuffed into the hole and
shored into place from the inside. The array of rubber leak stoppers,
coir mats and Plasticene (yes) that the Sunderland carried for such
eventualities was unequal to the occasion.
The flight engineer who accomplished this work during the flight back
to Hobsonville was later decorated for his troubles. To do it he had
hung precariously for hours by his heels - literally - from the decking
support cross-members, upside down in the bilges, packing whatever was
to hand into the hole and surrounds. It wasn't sufficient only to try
to reduce the inflow of water that was inevitable when the aircraft
touched down on the seaway at Hobsonville. What could not be assessed
with confidence was the possibility that the hydraulic force of the
water on touchdown at 80 knots might rip the weakened structure wide
open. Thus the engineer had to do whatever he could to shore it all up.
The duty crew at Hobsonville and anyone else who happened to be
standing around on that Sunday were called out. Several seaplane
tenders - flat-bottomed barges with lowish freeboard - were prepared.
Aboard was the beaching gear and high-capacity powered Climax water
pumps. The beaching gear was a pair of wheeled bogies mounted on
substantial girders that fitted onto a hard point in the armpit of each
wing and were then snibbed to the respective side of the fuselage.
There were no modern labour-saving devices or other niceties to this.
Heavy pushme-pullyou functionality was the watchword.
When fitted the wheels projected below the lowest point of the hull so
the aircraft could be winched up the slipway. They were hauled up the
ramp backwards by a wire hawser bolted through a ring under the tail.
As they rose out of the water onto land in such an undignified manner
the persona of these great things, whose elegance in either of the two
elements for which they were designed was unsurpassed, seemed
invariably to shrink into embarrassment.
The Sunderland carried two water pumps as part of its standard internal
kit. One was powered by the auxiliary power unit (APU), a small petrol
engine that lived in the starboard leading-edge wing root. The other
was a hand pump stowed in the bow compartment. The latter looked like
a vehicle tyre pump, except that the working stroke was the pull not
the push. It was exceedingly hard work. For other than the most
trivial of tasks, using it called for approximately the same optimism
as baling out Lake Taupo with a bucket.
The APU pump was scarcely any better. The APU could not be started
until the aircraft came to rest because its housing in the wing root
had to be opened from the outside to allow the engine to breathe and
the exhaust to escape overboard. To accomplish that task one had to
climb out of a hatch in the fuselage roof, step from the curved top
surface of the fuselage onto the wing, undo the Dzus fasteners that
held everything closed, and open the hatch in the leading edge; all of
this proximate to the inboard engine nacelle and propeller. It was not
a manoeuvre to be recommended if the aircraft was in significant motion
including lumpiness in the seaway - unless of course one wished to go
swimming involutarily (having taken one's chances through the propeller
arc).
The capacity of the APU pump was greater than the hand pump of course,
but its reliability was awful. Bilge water generally is not pretty
stuff. Not only does it smell bad, but to varying degrees it
accumulates oil and other contaminants, both fluid and solid. To
protect the pump mechanism (and the APU itself from overload, for it
had other uses) the associated plumbing was filtered. The filters
choked quickly on a diet of bilge soup. Memory dims a little, but
recollection is that two or three minutes was a respectable run; five
minutes or ten was exceptional.
Out of these considerations, prudence called for the supplementary
barge-mounted Climax pumps to be available. This was high-capacity
equipment, in the class of the average fire hose. The units had been
started and tested ashore before the aircraft alighted. All was as
ready as it was likely to be.
The aircraft touched down in the channel. The hull was not further
breached. But the water did come in - and fast.
Then intervened Sod's Law. Not Murphy's; Sod's. The two are
different, though often they are confused with each other. In aviation
at least, Murphy states that if any important component is designed
with the potential to be assembled wrongly, someone some day will
manage to gratify the potential. Sod is simpler; if something can go
wrong, it will.
The plan was that the supplementary pumps would at least hold the flow
while the beaching gear was strapped on. It should have worked. What
went wrong, however, was that the Climax pumps so recently tested would
not start. The onboard APU pump quickly expired, as expected - it could
not cope with the flow anyway. The hand pump was useless. The aircraft
started to sink.
The space beneath the lower deck of a Sunderland - the bilge - was
compartmentalised into watertight sections. The deck itself, however,
was close to or below the static waterline. Above the deck in the
doorways between compartments, therefore, and aligned with the lateral
bulkheads beneath the decking, there were low doors that could be
dogged shut. Called swash doors, they stood three feet or so high, and
they carried the watertight compartmentalisation on up to the
level of their tops.
On this occasion the waters rose inside and began to lap over the swash
doors. Re-starting the main engines and simply running the aircraft
onto the mud flats under power started to become a serious option.
Then one of the Climaxes cleared its throat and decided to behave; then
another. With the whole interior now awash to well above the tops of
the swash doors, these pumps were able to stabilise the water level.
Now came a final difficulty. The aircraft of course had settled well
down. Both wing floats were in the water. Indeed their buoyancy was
helping prevent matters getting worse. The hull was now so low,
however, that the very high buoyancy of the big pneumatic tyres made it
impossible to force the beaching gear far enough under the surface to
engage the tops of the legs into the sockets under the wings.
So, further delay ensued while air was let out of the tyres.
Eventually the aircraft was inched up the slipway on the rims of the
wheels, which became easier and easier as the goodly part of the inner
harbour then inside the aircraft spilled out of the hole through which
it had entered. No fish, though.
Some air show indeed .......
Most tales have a moral, and this one is no exception. It is not a
tale cautionary about Tail Number 13, however. Nor is it that landing a
seaplane on a runway is a bad idea - which is not a moral but a
self-evident truth.
The real moral is about plans. The train of events after the touchdown
suggests there is another rule that ranks alongside Murphy and Sod. No
matter how well-conceived a plan may be to take us from the known to
the unknown, expecting its execution from start to finish to follow the
pattern prescribed for it is the really bad idea. The best any plan can
do is provide a point for considered departure when the unexpected
happens, as happen it will. A larger Lesson for Life, perhaps?
In a nutshell, stay flexible.
PS: See also
and
Wellington's new pride and joy, the virgin runway fortified at each
end against the sea at Rongotai. Go back in events to the air show
staged to mark the opening thereof.
The show was supposed to have been on the Saturday, but Wellington's
weather was in one of its more sullen tempers on that day. The Sunday
dawned better, but not much. No rain or significant cloud, but a very
strong, very gusty nor'westerly gale swinging twenty degrees misaligned
with the runway.
Sunderland flying-boat NZ4113 was charged with a flypast along the
runway to open the show, thence to patrol Cook Strait as
search-and-rescue picket for the rest of the afternoon (inelegantly,
the callsign assigned for the latter purpose was Duckbutt).
My log book reads copilot and, with tactful understatement, records the
manoeuvre as "Touch and Go, Rongotai". The planing hull was breached
in the process. Having become a casualty itself, the aircraft was
obliged to abandon the duckbutt duty in favour of a duckscuttle back
home to Hobsonville.
But before turning to the detail, let me mention an aircraft
that followed us in the programme, a Royal Air Force Vulcan,
tail number XH498. On approach from the south in the tumultuous wind
this aircraft hit the lip of the runway where it falls away into the
sea. One undercarriage leg broke at its root. Though it remained
attached to the aircraft it was free to flap in the breeze - and did.
Fuel lines were ruptured, releasing turbine kerosene to spray
everywhere as the aircraft climbed away. The hapless machine landed at
Ohakea. As expected the damaged leg collapsed during the runout. The
aircraft slewed off the runway on one wheel and the other wingtip,
ploughing up the turf before coming safely to rest. It was repaired at
Ohakea over the next several months, and eventually was flown back to
Britain.
Some show. Some opening. Double trouble.
As the Sunderland sullied the spotless new seal, the sensation from the
cockpit was just a brief couple of mild bumps - rather like a car
negotiating a double speed hump. From the lower deck, however, the
sandpapering noises were louder, more prolonged, and much more
alarming.
The hole was a couple of feet long or thereabouts and about half that
in width. It was big enough to be a worry, shaped like an isosceles
triangle with the pointy end forward. Trapped bilge water sprayed out.
The lowest point of the keel, right at the "step" in the planing
surface, had been ground away. The void was at a junction of several
compound curves in the frames and aircraft skin, and was both too large
and too irregular to plug satisfactorily in the air. (It was also a
bitch to repair later.)
As it happened, the aircraft was rigged for a return passenger run to
the Chathams. At the time, these flights plied about once a month
between Evans Bay and the Te Whanga Lagoon by direction of the
Government; the Member for Lyttelton (which included the Chathams) was
the burly, bluff and highly engaging Norman Kirk. For students of the
history of the New Zealand coastal shipping trade, these flights were
conducted under charter to the then famed Holm Shipping Company.
The substantial land airfield that's now near Waitangi came later.
Meantime the Sunderlands provided an air bridge. (As an aside, a
couple of weeks or so after the events related here we lost a
Sunderland in the lagoon. Whilst taxying where it was thought to be
safe on the line of the lead-in markers, there was an argument with a
submerged and uncharted rock. The rock won. There were no casualties
but the aircraft was kaput; sunk; gone to Davy Jones.)
The significance of the Chathams rig in the context of the runway
touchdown was that the wardroom and another compartment further aft
were converted for passengers. Ordinary airliner seats were installed.
Needs must; their squabs were put to a use their designer could never
have intended nor even envisaged. They were stuffed into the hole and
shored into place from the inside. The array of rubber leak stoppers,
coir mats and Plasticene (yes) that the Sunderland carried for such
eventualities was unequal to the occasion.
The flight engineer who accomplished this work during the flight back
to Hobsonville was later decorated for his troubles. To do it he had
hung precariously for hours by his heels - literally - from the decking
support cross-members, upside down in the bilges, packing whatever was
to hand into the hole and surrounds. It wasn't sufficient only to try
to reduce the inflow of water that was inevitable when the aircraft
touched down on the seaway at Hobsonville. What could not be assessed
with confidence was the possibility that the hydraulic force of the
water on touchdown at 80 knots might rip the weakened structure wide
open. Thus the engineer had to do whatever he could to shore it all up.
The duty crew at Hobsonville and anyone else who happened to be
standing around on that Sunday were called out. Several seaplane
tenders - flat-bottomed barges with lowish freeboard - were prepared.
Aboard was the beaching gear and high-capacity powered Climax water
pumps. The beaching gear was a pair of wheeled bogies mounted on
substantial girders that fitted onto a hard point in the armpit of each
wing and were then snibbed to the respective side of the fuselage.
There were no modern labour-saving devices or other niceties to this.
Heavy pushme-pullyou functionality was the watchword.
When fitted the wheels projected below the lowest point of the hull so
the aircraft could be winched up the slipway. They were hauled up the
ramp backwards by a wire hawser bolted through a ring under the tail.
As they rose out of the water onto land in such an undignified manner
the persona of these great things, whose elegance in either of the two
elements for which they were designed was unsurpassed, seemed
invariably to shrink into embarrassment.
The Sunderland carried two water pumps as part of its standard internal
kit. One was powered by the auxiliary power unit (APU), a small petrol
engine that lived in the starboard leading-edge wing root. The other
was a hand pump stowed in the bow compartment. The latter looked like
a vehicle tyre pump, except that the working stroke was the pull not
the push. It was exceedingly hard work. For other than the most
trivial of tasks, using it called for approximately the same optimism
as baling out Lake Taupo with a bucket.
The APU pump was scarcely any better. The APU could not be started
until the aircraft came to rest because its housing in the wing root
had to be opened from the outside to allow the engine to breathe and
the exhaust to escape overboard. To accomplish that task one had to
climb out of a hatch in the fuselage roof, step from the curved top
surface of the fuselage onto the wing, undo the Dzus fasteners that
held everything closed, and open the hatch in the leading edge; all of
this proximate to the inboard engine nacelle and propeller. It was not
a manoeuvre to be recommended if the aircraft was in significant motion
including lumpiness in the seaway - unless of course one wished to go
swimming involutarily (having taken one's chances through the propeller
arc).
The capacity of the APU pump was greater than the hand pump of course,
but its reliability was awful. Bilge water generally is not pretty
stuff. Not only does it smell bad, but to varying degrees it
accumulates oil and other contaminants, both fluid and solid. To
protect the pump mechanism (and the APU itself from overload, for it
had other uses) the associated plumbing was filtered. The filters
choked quickly on a diet of bilge soup. Memory dims a little, but
recollection is that two or three minutes was a respectable run; five
minutes or ten was exceptional.
Out of these considerations, prudence called for the supplementary
barge-mounted Climax pumps to be available. This was high-capacity
equipment, in the class of the average fire hose. The units had been
started and tested ashore before the aircraft alighted. All was as
ready as it was likely to be.
The aircraft touched down in the channel. The hull was not further
breached. But the water did come in - and fast.
Then intervened Sod's Law. Not Murphy's; Sod's. The two are
different, though often they are confused with each other. In aviation
at least, Murphy states that if any important component is designed
with the potential to be assembled wrongly, someone some day will
manage to gratify the potential. Sod is simpler; if something can go
wrong, it will.
The plan was that the supplementary pumps would at least hold the flow
while the beaching gear was strapped on. It should have worked. What
went wrong, however, was that the Climax pumps so recently tested would
not start. The onboard APU pump quickly expired, as expected - it could
not cope with the flow anyway. The hand pump was useless. The aircraft
started to sink.
The space beneath the lower deck of a Sunderland - the bilge - was
compartmentalised into watertight sections. The deck itself, however,
was close to or below the static waterline. Above the deck in the
doorways between compartments, therefore, and aligned with the lateral
bulkheads beneath the decking, there were low doors that could be
dogged shut. Called swash doors, they stood three feet or so high, and
they carried the watertight compartmentalisation on up to the
level of their tops.
On this occasion the waters rose inside and began to lap over the swash
doors. Re-starting the main engines and simply running the aircraft
onto the mud flats under power started to become a serious option.
Then one of the Climaxes cleared its throat and decided to behave; then
another. With the whole interior now awash to well above the tops of
the swash doors, these pumps were able to stabilise the water level.
Now came a final difficulty. The aircraft of course had settled well
down. Both wing floats were in the water. Indeed their buoyancy was
helping prevent matters getting worse. The hull was now so low,
however, that the very high buoyancy of the big pneumatic tyres made it
impossible to force the beaching gear far enough under the surface to
engage the tops of the legs into the sockets under the wings.
So, further delay ensued while air was let out of the tyres.
Eventually the aircraft was inched up the slipway on the rims of the
wheels, which became easier and easier as the goodly part of the inner
harbour then inside the aircraft spilled out of the hole through which
it had entered. No fish, though.
Some air show indeed .......
Most tales have a moral, and this one is no exception. It is not a
tale cautionary about Tail Number 13, however. Nor is it that landing a
seaplane on a runway is a bad idea - which is not a moral but a
self-evident truth.
The real moral is about plans. The train of events after the touchdown
suggests there is another rule that ranks alongside Murphy and Sod. No
matter how well-conceived a plan may be to take us from the known to
the unknown, expecting its execution from start to finish to follow the
pattern prescribed for it is the really bad idea. The best any plan can
do is provide a point for considered departure when the unexpected
happens, as happen it will. A larger Lesson for Life, perhaps?
In a nutshell, stay flexible.
PS: See also
and
It is located on the upper reaches of Aucklands Waitemata Harbour, not far from Whenuapai, so the aircraft did operate off salt water.