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John Laming |
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| About the Author ... |
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John Laming is British
by birth, but migrated to Australia in 1947 at age 16. He spent the war years as
a boy in Kent, England, and thus witnessed firsthand the Battle of Britain air
battles. He entered the Royal Australian Air Force in 1951, and remained in the
RAAF until 1969. There, he flew fighters, bombers and transports, and was
awarded the Air Force Cross. After leaving the military, he spent seven years
with the Australian Department of Civil Aviation, flying DC3s and F27s doing
flight calibration testing of navaids around Australia and New Guinea.
Laming's airline career began in 1976 when he joined Air Nauru to fly
Boeing 737-200s around many exotic Pacific islands, including Solomon Islands
(Guadalcanal of wartime fame), Tarawa, Marshal Islands, Guam, Truk, Saipan,
Palau, Fiji, Samoa, Cook Islands, New Caledonia, Manila, Hong Kong, Japan and
other areas. In 1988, he returned to England and flew 737s for Paramount
Airlines around Europe and Middle East. After that, he spent a year flying for
German operator Hapag-Lloyd on Boeing 737-400s and -500s.
Upon reaching mandatory retirement at age 60, Laming returned home to
Melbourne, Australia, and took up instructing on singles and twins. He also does
occasional contract work as a simulator instructor on the B737-700 at the SAS
Flight Academy at Stockholm, and does consulting work on aircraft accident
investigation cases.
John Laming is married, and has two children. His son (37) presently
flies as FO on the 737-400 with his old company Air Nauru. Now in his late 60s,
John remains fit, renews his instrument rating annually, and hopes to stay
active in aviation for many years to come. These days, his greatest pleasure is
to hop into a Boeing 737 simulator and fly it single-pilot. He says he knows
it's not the real thing, but reports that there is no greater sense of
achievement than to know that he can still hack a single-engine ILS in a 25-knot
cross-wind at night.
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In
writing this article, I am reminded of the often-used patter by young
instructors in which the student is told to keep an eye on the engine
temperatures and pressures during the takeoff. The reality is that oil and
cylinder head temperatures are slow to indicate trouble, while oil pressure
needles can flicker and vary by small amounts depending on engine power and RPM.
A sudden drop of oil pressure near liftoff could be an impending engine failure
or a gauge malfunction, but there is simply no way of knowing for certain. A
late abort for an engine gauge reading, when combined with a limiting runway
length, has all the potential for an overrun accident.
The correct time for a last-minute assessment of engine health is at brake
release, with priority then given to directional control, lookout, and airspeed
indications. Good airmanship dictates that a critical stop/go decision should
not normally be based upon one gauge alone. Always check for corroborative
evidence before committing yourself to an irrevocable course of action.
The following incident happened on a dark Pacific night, where a seemingly
impossible combination of factors caused a B737 to come just a few seconds away
from disaster.
Air Nauru...
The
best job I ever had was flying a Boeing 737 for a small airline, which was based
on the tiny island nation of Nauru just 27 miles from the equator in the Central
Pacific. The nearest daytime alternate was 375 miles away and a night diversion
meant 500 miles to the Marshall Islands, or the burning of one's bridges of two
hours island holding fuel, followed by landing or ditching! Our destinations
included many of the Pacific islands between Hong Kong and Honolulu, the
Solomons to Rarotonga, and New Zealand to Fiji. Our air hostesses all spoke
English in a variety of charming regional accents and many were natural dancers
who had been taught from childhood that music, laughter, and dancing was all
that was needed to enjoy a full life.
We flew the popular Boeing 737 with most of the pilots expert at short-runway
operations and black-hole approaches to remote islands. Some of us had been
trained in the Royal Australian Air Force (RAAF) and our number included
experienced ex-fighter and transport pilots. Other pilots included Americans and
Kiwis, while the remainder were Australian GA pilots who had been employed on
charter and instructor flying before getting that lucky break into an airline.
The runway on our island base was 5600 feet long, with a road cutting across
only feet from each end. The overrun area was just 100 feet from the ocean, with
the prospect of fatal damage if the aircraft collided with huge phosphate rock
boulders which formed the sea wall. In the wet season, strong southerlies meant
crosswinds up to 30 knots while huge waves whipped up by the winds dashed
themselves against the rocks, sending mist and spray over the threshold.
...and Air Florida
Readers
may remember a widely publicized 1982 accident involving Air Florida Flight 90,
a Boeing 737 that crashed on takeoff from Washington National Airport as it
tried to get airborne while covered in snow and ice. The aircraft was unable to
hold altitude and, after hitting a bridge, crashed nose first into the frozen
Potomac River. The FDR was recovered and its evidence showed that the engines
had not delivered full takeoff power during the takeoff. The engine power
indicators had given false information to the crew, possibly due to ice blocking
air inlet tubes which, in turn, sensed the power delivered. These tubes, which
have an opening the size of a drinking straw, measure the pressure of air being
drawn in by the engine compressors, and compare it to the pressure increase due
to combustion which is pushed out at the back of the engine. Known as PT2
sensing tubes, they show the engine pressure ratio (EPR) on a cockpit gauge.
(See CVR Transcript.)
In simple terms, if the front tube is blocked, the sensor thinks no air is
coming into the front of the engine. The rear sensor, operating normally, senses
lots of high-pressure hot air being ejected from the tail pipe and thus the EPR
will indicate an abnormally high reading. The natural tendency to remedy the
apparent excessive power indication on the EPR gauges is for the pilot to ease
the throttles back in order to keep within perceived engine limits. The engine
RPM gauge will, however, show the pilot the real power being produced.
Obviously, if 100% RPM is indicated, the engine is really pushing out lots of
power, regardless of a false reading on the EPR gauge caused by a blocked PT2
tube. The advantage of the EPR gauge is that accurate power settings can be
measured, providing of course that the system works as advertised.
Following the lengthy investigation into the Potomac accident, notices were
sent to all operators of Pratt & Whitney JT8D series engines, warning that
crews should be on alert for erroneous EPR indications in icing conditions and
to rely primarily on the engine RPM gauge for actual indications of power.
Typically, the RPM gauge is called an N1 or Fan gauge and will usually show 35%
N1 while idling, 83% in cruise, and 95% — 101% on takeoff. Blocking of PT2
tubes by substances other than ice was not discussed in the Alert Bulletin.
Boeing recommended that the crew calculate the expected EPR and N1 gauge
readings for each takeoff. These readings, which are placed on a takeoff data
card, will vary, depending on the takeoff weight of the aircraft, length of
runway, ambient air temperature, and aerodrome pressure altitude. Also on the
card will be the V1 decision speed, rotation speed, and other information
pertaining to the takeoff.
An interesting situation
The following episode began when I was rostered to fly as a passenger on a
nonstop night flight to Guam in the Western Pacific. Flight time was four hours
and, on arrival at Guam in the early morning, I had planned to catch some sleep
at The Hilton Hotel before crewing another flight to Manila.
There were 60 passengers including some deadhead crew on the flight and,
after boarding, I settled into a first-class seat, adjusted my reading glasses,
and watched the senior hostess brief her cabin crew as the engines were started.
A few minutes later, at 0130 local time, the aircraft moved onto the runway,
back-taxiing for takeoff to the northwest. From my window seat, I could see a
line of cars on the nearby road only 50 yards from the runway. The flashing blue
light on a traffic policeman's motorbike indicated that he had stopped all
traffic to prevent anyone getting blown off the road by the jet blast on
takeoff.
A few seconds later, the senior hostess came to me and said that the captain
had invited me up front for takeoff. Like most pilots, I welcomed the chance of
observing the action from the cockpit and, leaving my reading glasses on the
seat next to me, I entered the darkened flight deck, quickly sat on the
jumpseat, and thanked the captain, whom I had trained for his command some
months earlier.
The first officer was to carry out the takeoff and I caught the last part of
the emergency briefing as we slowly turned to line up. The takeoff data card
indicated 10 degrees of flap for takeoff, V1 of 130 knots, VR (rotate) speed of
135 knots, and initial climb speed of 145 knots. Even without reading glasses, I
could plainly see the EPR gauge digital cursors set for 2.18 EPR, which meant
maximum takeoff power was needed. This was understandable, considering the short
runway, the hot night, and the extra fuel needed for a long flight. The data
card also showed that the crew had calculated 100% N1 was needed for takeoff,
and this tied in with the 2.18 EPR limit. The N1 gauges were dimly lit and I
could not see the needles clearly without my glasses, which I had left back in
the cabin.
The traffic officer's blue strobe light was still flickering on the road
ahead and, from our position on the runway threshold, I could just make out the
surf of the Pacific a few feet behind us and the dark shape of the control tower
some two thirds down the runway and just off the parallel main road. From
previous experience, I knew that the indicated airspeed should be around 120
knots as the aircraft passed abeam the tower, with liftoff speed usually 10
seconds later.
Takeoff power
The captain opened the throttles to 1.6 EPR with brakes set, checked that
both engines spooled up evenly, then quickly advanced the throttles to the
planned takeoff power of 2.18 EPR. The brakes were released and the first
officer began to steer the aircraft down the runway centerline. Acceleration
appeared normal, and I could clearly see both EPR gauges steady at 2.18. The
airspeed indicator needle began to accelerate past 60 knots and I checked all
engine gauges in a swift eye scan. Fuel flow, N1, and exhaust gas temperature (EGT)
were all pointing in the right area, although somewhat blurred to my vision
without my glasses. Seconds passed and the captain called "80 knots"
as the dual airspeed indicator check. A sixth sense warned me that the
acceleration was not the solid kick in the back that I would have expected from
2.18 EPR, and at the same instant I noticed the captain begin to glance rapidly
from the instruments to the remaining runway ahead. There was no readily
discernible problem but I had an uneasy feeling that something was not quite
right.
The company procedure was that, apart from the 80 knot airspeed check, no
calls were to be made by either pilot unless something was seriously amiss. On
this occasion, the takeoff seemed to proceeding normally and, apart from my
vague unease at the perceived lack of marked acceleration, I was unable to
pinpoint any impending problem.
The control tower and passenger terminal building flashed past the right wing
tip, as I strained forward against my shoulder straps in an attempt to focus
more clearly on the vital N1 gauges. The EPR needles were clear — exactly 2.18,
but again I could not get an accurate look at the N1 without glasses. The
airspeed reading went through 110 knots, we should have been perhaps 10 knots
faster from my experience, and my unease grew stronger. One thing was happening
for sure, and that was we were rapidly using up the remaining runway. Six runway
lights to go, and we were still at least 10 knots below V1, the go/stop decision
speed. It was, to say the least, an interesting situation, and I hoped that the
captain would not make a split-second decision to abort the takeoff because we
could now never pull up in time, even with maximum reverse thrust and braking.
Our V1 speed was useless now, and the invisible sea swept rocks were only
seconds ahead.
My unease had just changed into the cold realization that we were never going
to attain liftoff speed before reaching the end of the runway, when suddenly the
captain urgently called "ROTATE NOW!" and while hauling back on the
control column he pushed both throttles hard against their forward stops. Boeing
terms this "firewalling the thrust levers," to be used as a last
resort to climb out of trouble.
The last runway light disappeared under us, as did a fleeting close-up sight
of the brilliant blue flashing strobe light of a shocked traffic cop's
motorbike. I felt the reassuring surge of thrust propel the 737 upwards at a
deck angle of 20 degrees, and silently thanked the Lord that the captain had
made an instant correct decision to firewall those Pratt & Whitneys. I knew
that the Potomac accident might have been averted if the crew had only hit the
throttles wide open to the stops, to prevent their ice-laden Boeing from
stalling.
We were later told that the flight data recorder showed that the aircraft had
lifted off at 15 knots BELOW the calculated VR rotation speed, and that the
aircraft had flown just 19 feet above the sea for several hundred yards before
gradually climbing away. We never did see the towering metal structure of the
phosphate cantilevers that passed above our altitude, and situated 200 yards to
the right of the extended runway centerline...
What's wrong with this picture?
Ahead was sheer blackness, and the captain locked on to instruments as the
ASI needle crept towards safe flap-retraction speed. The VSI was held at 1000
fpm, and the first officer set the climb thrust at 1.93 EPR as the flaps were
slowly retracted in sequence. It seemed an abnormally long time before the
aircraft reached 250 knots, which was the scheduled climb speed that night, and
the rate of climb was well below normal. Finally we passed 5,000 ft, engaged the
autopilot, and called for coffee while we held a roundtable conference on the
recent events. The mechanic who had been seated in the cabin came up front and
said that a couple of deadheading pilots down the back sent their respects to
the captain, but they hoped he had finished playing silly buggers with the
aircraft as they were hoping to get some shut eye! They had obviously felt the
thrust change through the seat of their pants.
We turned our attention to a detailed scan of the engine instruments and the
mechanic remarked that the N1 indications seemed low when compared with the 1.93
EPR climb setting. From the back of my mind came the recollections of previous
problems that I had experienced several months ago with an over-reading EPR
gauge. On the first occasion, we had just attained takeoff thrust early in the
roll, when one EPR needle moved to an apparent overboost figure of 2.35 EPR,
while the second needle stayed steady at the planned 2.10 EPR. The other engine
parameters were normal for takeoff and, in particular, both engines were turning
up nicely at 100% N1. Clearly the problem was a faulty EPR indication and, as
our speed was only 50 knots, I decided to reject the takeoff and return to the
terminal for a chat with the mechanics. A check of the PT2 tube, plus an engine
run up, indicated the problem had cleared itself and we departed an hour later.
More recently, at 100 knots on takeoff, a similar fault occurred and this
time, the F/O urgently called that the engine was over speeding. He attempted to
pull back the throttle on that engine to limit the peak EPR, but I quickly
stopped his hand and told him to ignore the faulty reading. He was convinced
however, that the engine was overboosting because of the high EPR reading,
although I felt no asymmetric yaw on the flight controls. I again prevented him
from dragging the offending EPR back and we continued the takeoff using the N1
RPM (which was steady at normal takeoff thrust). Once at a safe altitude, I
turned on the hot air bleed system to the engine anti-ice, and almost
immediately the offending EPR needle did a few cartwheels and returned to
normal. We were not in icing conditions but the hot air used for de-icing had
obviously cleared some obstruction in the PT2 tube. The flight was continued
without further incident.
Back now to the present situation, where early indications of long-distance
storm activity began to show up on the weather radar screen. The storm tops were
around 35,000 feet, and at our dismal rate of climb we would be in the thick of
things in the next 20 minutes.
With the throttles set at the computed climb EPR, it was readily apparent
that both N1 readings of 88% and commensurate low fuel flows meant that some
common denominator was affecting both engines at the same time. We discussed
fuel contamination but decided that it was unlikely, given that the engines had
delivered maximum available overboost when the throttles had been firewalled
earlier. I gave fleeting thought to the possibility of EPR gauge malfunction,
especially after my previous experience with this problem, and knowledge of the
Potomac accident. With a warm airport temperature of 30 degrees centigrade,
icing of the PT2 tubes could be discounted and, in any case, it would be highly
unlikely that an identical malfunction would affect both PT2 tubes
simultaneously.
On my suggestion, the captain momentarily switched on the engine anti-ice to
both engines. This would normally cause a small loss of about 5% N1 and an EPR
drop of .08, which reflected the stealing of some hot compressor air for piping
to the engine inlet cowls and PT2 tubes.
The N1 dropped obediently but both EPR gauges went crazy, increasing by an
unheard of amount, and in the opposite direction to that expected. My mind went
back to a paragraph in the Potomac accident report which mentioned that with the
engine anti-ice switched on and PT2 tube blocked, the EPR needle would indicate
a reverse reading to that expected. Thus, tonight, the impossible had apparently
occurred: an identical erroneous reading on both EPR gauges at the same time.
The PT2 tubes were obviously still blocked but we now knew for sure that both
engines were operating normally. The decision was made to return to land and, at
500 feet, the landing lights were switched on, illuminating drifting mists of
phosphate dust from the nearby mine. The touchdown was perfect, right on the
1000-foot runway marker. Well-coordinated reverse thrust and braking gave nice
cool brakes on arrival back at the terminal.
Diagnosis
As the passengers disembarked to wait out the delay in the airport terminal,
mechanics had already removed the engine nose cones in order to check out the
PT2 system. With the aid of a flashlight, the cause of our troubles was soon
discovered. The PT2 tubes of both engines — the sensors that gave the vital
Engine Pressure Ratio readings for takeoff — were blocked, not with ice but
with congealed phosphate dust and some other glutinous substance. It was
impossible to determine the precise time that the tubes became blocked, or how
the substance found its way into the system.
At dawn a few hours later, early workers driving past the departure end of
the runway were the first to see debris from the coast road and nearby cliff
face rocks, blasted back over the threshold by the jet efflux of the 737. Black
skid marks on the road showed where the traffic policeman had burned up rubber
in a spectacular scramble for safety.
Later calculations showed that the actual power on takeoff was around 2.05
EPR, even though the EPR needles were steady at 2.18. That power would have been
ample for a long runway, and in fact was a setting frequently used for the right
combination of runway length and gross takeoff weight. The N1 gauge scale
between 91% and 100% is less than 3mm and very difficult to read in dim light,
especially at a quick glance. This might explain why the crew was unable to pick
the apparent lower-than-normal N1 readings on the takeoff run. At night
especially, it is also impossible to make any meaningful correlation between
rate of acceleration and runway remaining. Until it is almost too late, that is.
Several months afterwards, I read a report that described an incident on a
Boeing 727 that departed at night from a U.S. airport. The aircraft used 9000
feet of runway and during rotation, it wiped out the ILS localizer antenna
situated more than 1000 feet beyond the overrun area. The aircraft was damaged
but continued to fly. Investigation revealed that icing conditions had prevailed
and the crew had failed to actuate the engine anti-ice switches for takeoff. All
the PT2 tubes had iced up during the takeoff roll, giving significant EPR gauge
error. The crew did not detect any acceleration problem until almost too late
and also did not firewall the throttles.
Later versions of the Boeing 737 have CFM56 engines which rely on N1 gauges
as the primary power indication. EPR gauges still remain on many older jet
transports, however.
Aftermath
Following the incident on Nauru, the chief pilot suspended the captain from
flying duties. There was no in-depth investigation — only the personal opinion
of the chief pilot. In his report to the President of Nauru, who also held the
position of Minister for Civil Aviation, the chief pilot recommended that the
captain be downgraded to first officer permanently. This type of unilateral
action by the chief pilot was typical of the way he operated the airline, and
there was no effective avenue of appeal available to anyone unfortunate enough
to cross swords with the management pilots.
As I explained earlier, the phenomenon of unreliable EPR readings on takeoff
had occurred to me and other pilots, and although these had been reported
through official channels to management, there had been no revisions to the
operations manual warning of the specific problem. Some information had been
casually disseminated over beers at the bar of the local pub.
The Civil Aviation Department of Nauru consisted then of only two
individuals: the Director and a Project Officer. Neither had aeronautical
experience, both being more-or-less political appointees. Hence any advice on
operational matters was sought directly from the chief pilot, and his advice was
then rubber-stamped. Operational surveillance of the airline was carried out by
civil aviation authorities from New Zealand. This meant that a flight operations
inspector from New Zealand would occasionally fly with a crew on a scheduled
flight. Reports on flight crew performance were generally very good, although
there was sometimes mild criticism of the administration and support services.
The maintenance of the aircraft was the responsibility of Air New Zealand, and
this really was first class in all respects. The government of Nauru spared no
expense in this regard.
When I heard that the captain had been demoted, I contacted the chief pilot
to register a strong protest at this unfair action. The word had quickly got
around the rest of the aircrew that the captain had been shafted, but apart from
a few sullen mumbles out of the earshot of management, not one pilot had openly
questioned the motives behind the management's decision. Job security was the
name of the game. The deputy chief pilot was a clone of his boss, and in fact
had been the first person to meet the aircraft after its immediate return to
Nauru on the night of the incident.
Aware of the fact that someone is always the scapegoat in this type of
situation, I had vacated the cockpit after landing, and was sitting innocently
in a passenger seat when the deputy chief pilot boarded the aircraft on its
return. He was therefore unaware of my presence in the jump seat when the fun
and games had started. I had advised the captain to let me know if he needed my
backing as a witness, as knowing the then-management style, there was a strong
chance that the captain would be pronounced guilty of a wrong operational
decision without a fair trial. For this reason I wanted to keep my powder dry
for any forthcoming stoush.
In my view as a direct witness, the captain had done an excellent job of
airmanship in his decision to firewall the throttles. The chances of an
identical double EPR failure at night, causing identical instrument readings,
were infinitesimally small, and it would be classically wise after the event to
blame the crew for not picking the problem. The actual power (EPR) used on that
night was similar to that used on an everyday reduced-thrust takeoff at longer
runways such as Hong Kong, Guam, Nandi or Sydney. The acceleration forces were
identical to a planned reduced-thrust takeoff, and it was only at a late stage
of the takeoff at Nauru that it was realized that the takeoff run was going to
be insufficient to lift off.
After the mechanics had dropped the engine cowls and discovered the blocked
EPR tubes, I had been witness to an extraordinary outburst from the deputy chief
pilot directed towards the captain. He was told that the incident was all his
fault, and to get the aircraft on its way to Guam as soon as the mechanics had
signed the paperwork.
On our arrival at Guam a few hours later, I was handed a message from Nauru
that I was to take over command of the return flight, and the other captain
would come home as a passenger. I suspected that the scene was being set up for
a kangaroo court. Later events proved I was right.
A few days later I was home in Melbourne on days off, when I heard that the
captain had been suspended indefinitely until the President of Nauru had made a
decision to terminate the captain's contract, or agree to the chief pilot's
recommendation to demote him for good. After connecting a tape recorder — I had
by now, little faith in justice — I telephoned the chief pilot in Nauru, and
protested strongly, stating that as an observer in the jumpseat, I thought the
captain should have been congratulated for having done the right thing at a most
critical time. The chief pilot warned me to keep out of the affair otherwise my
own future would be at risk. I replied that I had no intention of closing my
eyes to the matter, and that my report would go directly to the Minister for
Civil Aviation. The battle lines were drawn.
Escalation
I contacted the New Zealand flight operations inspector responsible for Air
Nauru, and explained the circumstances of the incident. His name was Captain Ian
Gemmel, himself a former chief pilot of Air New Zealand. Gemmel said he had only
sketchy details of the incident, gleaned from hangar talk by the Air New Zealand
mechanics who had recently returned from Nauru from their fortnightly tour of
duty. He had not received any direct report from Air Nauru management, which of
course included the chief pilot.
I explained that I had been aboard the 737 at the time, and he listened with
interest to my side of the story. He was very diplomatic, and careful not to
give any opinions on the telephone. I told him that the captain was under
suspension, but again he made no comment. When I suggested that he should
investigate the incident in the light of his position as our flight operations
inspector, he replied that protocol dictated that he wait until invited by the
Nauru Director of Civil Aviation to come to Nauru. I knew that wouldn't happen.
This was a dead-end conversation, but at least the inspector now knew the
facts, even though he could not (or would not) act to get a formal investigation
underway. Certainly he showed little interest in the fate of the captain. The
first officer, incidentally, was part of the management team drinking circle,
and escaped with a minor admonishment quickly forgotten over the next round of
drinks.
I next contacted Captain Belton, the then-Technical Director of the
Australian Federation of Air Pilots, known as the AFAP. Although Air Nauru
pilots could not belong to any industrial union by the terms of their contract
with Nauru, nevertheless the brotherhood of pilots meant that the AFAP would
help with advice if sought. The captain and myself were interviewed by Belton,
who showed great professional interest in the incident, especially with its
parallel in the fatal Potomac River B737 accident in the U.S. Ansett Airlines
subsequently advised their crews of the circumstances of the Air Nauru incident.
Belton then wrote to the Director of Civil Aviation (DCA) in Nauru expressing
concern at the treatment by management of the captain, stating that such
injustice would never be tolerated in Australian airlines. He urged the DCA to
release the captain from suspension and initiate a full technical investigation
of the incident. There was no reply from Nauru.
Politics
About that time, some hard decisions regarding the future of Air Nauru were
being debated in the Nauruan parliament. The airline was heavily subsidized by
the government, and was losing money. The chief pilot was told to dismiss half
of the total pilot workforce, and it was left to his discretion who got the
chop. About 15 pilots were given one week's notice, although there were rumors
that most of these would be rehired once the political crisis in parliament had
been resolved. The President of Nauru and his people were inordinately proud of
the airline and its crews, and it had been with great reluctance that the order
to dump crews had been sent down the line.
In situations like this, it would normally be last-on-first-off in order of
seniority with the company. I thought I would be safe. I was dead wrong. The
chief pilot first got rid of all those captains over the age of 50, except
himself. There were four of us, all senior in the airline. That neatly got rid
of a few thorns in his side with no bloodshed. Next went a few more captains and
first officers. One first officer had recently been recruited and had
volunteered for the secondary appointment of navigation officer. His job was to
update the office Jepp charts. He had only been in the airline for a few months,
but kept his job because he had a formal "title." He was also on
excellent terms with all the management captains.
Seniority or good service counted for nothing. One pilot sacked was the
captain of the EPR incident. He was already on suspension anyway. While in
limbo, he spent a lot of money on a Boeing 727 command endorsement, and got a
job flying a 727 for a Saudia Prince. He went from success to success and at the
time of writing is a senior captain with a well-known Australian airline.
The crews dismissed were not told on what basis their names were chosen. I
believe it was a night of the long knives. A few weeks later, there was good
news for some that were sacked, as Parliament authorized the rehiring of
everyone, subject to the chief pilot's choice. The knives were twisted when none
of the over-50s were hired, and were left to go on the dole in Australia. Soon
afterwards, more pilots were hired to replace the over-50s that had been sacked,
and first officers waiting in the wings were promoted in their place. There were
no airline jobs in Australia, and so I became a taxi driver, as did a few
others. My most bitter moments were waiting for customers in a taxi rank outside
Melbourne airport to find that my clients were newly-recruited Air Nauru pilots
hired to replace my colleagues and me.
Unfinished business
My last flight was a scheduled service from Nauru to Fiji and return.
Attempts on my part to get justice for the suspended captain had foundered. The
Nauruan DCA simply lacked the technical knowledge to adequately assess the
recommendations by the chief pilot that the captain be demoted. They saw that as
an internal matter between the captain and expatriate management. The captain
was dismissed as part of the sudden retrenchments, and the file closed. There
was no follow up by the New Zealand Civil Aviation inspector because he was
never invited for his opinion.
It was nighttime in Fiji as we loaded passengers for what was to be my last
flight with the company after 10 years of service. I was deep in thought as the
first officer set up the navigation systems. I could hear the soft voice of the
young Nauruan flight attendant as she welcomed her brood on board. The last of
the passengers arrived at the bottom of the airstairs, and I noticed that one of
them was a Nauruan cabinet minister whom I knew well. He had been the Director
of Civil Aviation when I first joined the airline all those years ago, and was
well regarded as a thorough gentleman. He was a qualified aeronautical engineer.
My own career with Air Nauru was to end with a final touchdown on Nauru in
four hours time, but now I saw an opportunity to clear up some unfinished
business. I was down the stairs in a flash, and greeting the minister like an
old friend, I took him aside and asked him if he was aware of the near accident
to the 737 a few weeks earlier. He looked puzzled when I told him that there
were certain aspects of the incident which I didn't like. He said Parliament had
been told by the Director of Civil Aviation that it was the captain's fault, and
that the dismissal was warranted. Ink was now dry on the rubber stamp.
I invited the minister to the cockpit for takeoff, but meanwhile showed him
the tiny air intake in the front of the 737's engines which had been blocked by
unknown debris on the night of the incident. I showed with a flashlight that any
blockage would be undetected because of the curvature of the PT2 tubes. He was
surprised that the blockage of such a tiny tube could cause a near disaster.
After he boarded, the senior flight attendant closed the front door, and
ushered him to the cockpit. I asked him to bear with me while I gave him a
thumbnail sketch of the EPR gauge operation, and backed it up by showing him the
schematic from the systems manual. All this time, the mechanics below were
patiently standing by to push the Boeing backward away from the airport
terminal, prior to our starting the engines. We were already late on schedule,
but I didn't give a damn.
I explained to the minister that the incident to the 737 had important
ramifications to future takeoff departures from Nauru, and that there was some
suspicion that the debris that had blocked the EPR tube contained phosphate dust
from the island mines. I then gave him a notepad and pencil, and asked him to
record the various engine instrument readings on takeoff. I was hoping to
convince him that on a night takeoff with dim instrument lighting, it was
possible to misread the main RPM gauges by a small amount. That small amount had
proved critical on the night in question, and fatal on the Potomac accident.
As an aeronautical engineer, he was aware of my explanations, and as we later
lined up for takeoff, I told him to read the gauges at 80 knots and at liftoff.
I opened the throttles to full thrust and as the airspeed reached 80 knots I
asked the minister to take down the EPR, N1, and fuel flow readings. He asked me
to turn up the instrument lighting, as he could not get an accurate reading. At
liftoff he again took the readings and complained that the N1 gauges (which give
the fan rotor speed in percent of RPM) were too hard to read at a quick glance.
I then reduced the power to climb thrust and asked for a final reading of the
three engine parameters.
Next I asked the minister to adjust the throttle settings to various
positions, and then asked him to call out the actual readings from the gauges.
By now he had got the message that on takeoff, it took more that just a
half-second glance to focus one's eyes at night on the critical engine power
instruments. With perhaps no more than three millimeters between a needle
indicating 93 percent and 100 percent power, it was possible to miss a
critically low power indication when the cockpit lighting was dim, as in a
darkened cockpit. The situation where the main engine EPR digital readout was
falsely displayed on the EPR gauge as full power only exacerbated the problem.
The aircraft was by now established on course for Nauru, and after engaging
the autopilot and double-checking that the ground-based navaids confirmed that
the aircraft inertial navigation systems were tracking correctly, I switched off
the seat belt signs and asked the flight attendant to send up the coffee. The
minister sat quietly, his eyes scanning the cockpit levers and instruments and
finally settling on the green glow of the weather radar screen. A few areas of
heavy rain clouds were inching towards us from the top of the 180-mile markers,
and I made a mental note to watch these radar echoes more closely in the next
ten minutes. Our senior flight attendant, who was from the Solomon Islands,
opened the cockpit door and delivered us three steaming cups of coffee. As she
closed the door and returned to the bright lights of the passenger cabin, the
minister said to me quietly, "Captain, what you are trying to tell me is
that you disagree with the opinion of the chief pilot in sacking the captain who
had the takeoff incident at Nauru?"
I chose my words carefully, as it was not my intention to come out with a
direct criticism of the chief pilot. This would conflict with the island culture
where it may be construed as poor manners to criticize one's immediate superior,
and any ill-chosen words could be counterproductive. I told the minister that he
had politics to contend with in his area of work, and that there was office
politics in the flying and operational of the airline.
I pointed out to him that a similar event had occurred in Washington D.C.,
where false engine readings, this time caused by ice blocking the engine
instrumentation, had caused the crash of Boeing 737 with many killed. The pilots
had failed to realize the cause of the problem until too late and the captain
had failed to firewall the throttles to power the 737 out of a stall. The
captain on the Air Nauru incident had acted quickly by advancing both throttles
to maximum available overboost and probably averted an otherwise-certain
accident. I added that there should be an independent technical investigation on
the incident, because as it was, the captain had, in the opinion of many Air
Nauru pilots, been unfairly dealt with by the chief pilot and others of the
management.
"What do you want me to do?" asked the minister. I replied that the
normal procedure would be to formally advise the New Zealand Civil Aviation
authorities of the circumstances of the incident, and ask them to send an
inspector to Nauru to interview the various people concerned. The minister
agreed to discuss the situation with his Cabinet colleagues. As I was about to
become unemployed in three hours, there was no more I could do except hope that
the minister would keep his word.
From gauges to radar
It was time to turn my attention to more immediate matters. The large clouds
on the radar screen were growing closer, and their ominously red centers on the
radar display indicated we would run into severe turbulence if the aircraft
maintained the direct track to Nauru. We were in thick cirrus cloud, which meant
that we were unable to visually navigate around the big stuff ahead, and were
now relying entirely on the radar to "see" the storms, and avoid them.
Over the years, the airline had experienced many failures of the radar, and
several aircraft had inadvertently flown directly into severe thunderstorms
without any warning. Radar spares were held in New Zealand and Australia and
could take several days to finally reach the aircraft. Due sometimes to
commercial pressures, and occasionally a misplaced sense of the macho, there
were captains who would invariably accept the aircraft without a serviceable
weather radar, and press on into the night risking thunderstorm penetration with
all its well-known hazards to flight safety.
I had been a passenger on some of these occasions, and had been scared
witless knowing that the radar was unserviceable. Passengers and flight
attendants were always blissfully unaware of the possible menace ahead. The
weather forecasts around the Pacific almost always warned of the presence of
occasional thunderstorms. Murphy's Law dictated that one of these would have
your name on it. Sod's Law amplified Murphy's which meant you could count on the
probability of blundering into a whole line of storms that were aligned with
your current track! There would be little warning until static electricity would
start to flicker in blue sparks over the windscreen, and next second there would
be savage buffeting and frightening turbulence. The knowledge that certain types
of thunderstorms could cause the destruction of an aircraft was ever in my mind
on those occasions, because the aircraft was flying blind and the crew counting
on statistics and luck to avoid the really bad storms.
The solution was easy, and that was to place radar spares at strategic ports
around the airline network. Guam and Nauru were the two hubs of our operations,
but the various management teams closed their eyes to the problem, and instead
relied upon captains to "cooperate" to keep the aircraft flying until
the spares caught up.
With these thoughts in my mind, and the presence of a captive minister in the
jump seat, I formulated a plan. If the plan was successful, it would mean a
safer operation of the airline. Either way, I had nothing to lose, because my
airline career was over — for the time being, that is.
The single thunderstorm (isolated, in meteorological terminology) was less
than 50 miles ahead and we were closing on it at 7 miles a minute. That meant in
7 minutes we were going to get beaten up by nature. Unless, of course, I steered
the aircraft around it.
Hitting the stopwatch, I quickly briefed the first officer of my intentions
through the headset communication system, without the minister hearing the
conversation. I then showed the minister how the radar controls worked, and
explained how to judge the severity of a storm by the various color codes on the
screen. I let him adjust the various radar control switches, adding that without
the radar we would not see the monster ahead. I then switched the radar to
standby, leaving a blank screen. The storm by now was 30 miles dead ahead, and
invisible to the three of us in the cockpit.
I told the minister that lack of suitable spares positioning around the
airline network meant aircraft were occasionally flying without operating radar
for several days. We operated broadly by Australian Air Navigation Orders, which
required Australian-registered aircraft to have an unserviceable radar repaired
at the next major servicing base, and in any case the aircraft must not be
operated in to areas where thunderstorms were forecast without a serviceable
radar. I explained that there were many servicing bases in Australia, and an
unserviceable radar was quickly replaced. This luxury was not available to our
crews because of the far-flung nature of the Air Nauru route structure, coupled
with reluctance to hold spares at intermediate airports.
I had my eye on the stopwatch, with three minutes left before I would turn
off course to miss the storm cloud ahead. The minister began to sweat a little,
as I explained that the blank screen in front of him represented an
unserviceable weather radar, and could he not see the danger of flying blind
without radar? Especially as we knew that there was indeed trouble ahead. I
explained that this then was the dilemma facing the captains who were forced
into the difficult choice of canceling a flight or accepting risks by keeping to
schedule.
To avoid these situations, we needed to place radar spares on Nauru and Guam,
I said. By now, the minister was getting tense, and so was the first officer.
Both knew that the storm was almost upon us, and the minister hinted that it was
high time the radar was switched on. I asked him to do the honors, and in a
flash he had switched the control knob from the standby position to on. Seconds
later, a solid red mass bloomed at 15 miles, and I began to turn the 737 to
starboard using the autopilot controls.
Hardly had the aircraft straightened out on the new heading, when the cloud
that we were in magically disappeared and we were bathed in light from a full
moon. Miles below there were hundreds of tiny cloud shadows on the Pacific, a
characteristic of this part of the ocean. There on our left a single monstrous
cloud towering from the ocean to 35,000 feet slid silently past the wing into
the darkness behind us. Lightning flickered and flashed deep inside its core and
I watched the face of the minister as he stared transfixed at the raw power of
nature.
"You have made your point, Captain," he said. "Now where do
you want those radar spares?"
Partial victory
A few weeks later, I was driving a taxi. I heard through the grapevine that
the New Zealand inspector had been invited to Nauru to investigate the takeoff
incident. His report exonerated the captain, and recommended that he be
commended for his actions in firewalling the throttles and thus preventing a
certain disaster. The inspector also made critical comment on the lack of
operational information in the company operations manual, following previous
instances of EPR tube blockage on takeoffs from Nauru.
The captain was not offered reinstatement despite the recommendations of the
inspector, and ten years later he has still received no official commendation
for his actions.
Radar spares were allocated to be held on Nauru, but not on Guam. Ah well,
you can't win them all, I suppose!
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