SA295 REVIEW MOTIVATION PART 1
ACCIDENT TO ZS-SAS BOEING 747-244B COMBI -FLIGHT SA 295, 27 NOVEMBER 1987.
A LOOK AT IN-FLIGHT FIRE INVESTIGATIONS SINCE 1987AND THEIR RELEVANCE TO A REVIEW OF THE HELDERBERG ACCIDENT
This entire article consists of 4 pages.
Links to pages 2, 3 and 4 as well as external supporting documents and video materials are at the base of this and subsequent pages.
I have now been researching and writing about aviation safety for more than 25 years.
In this time I have reviewed many thousands of documents relating to aircraft accidents. I have spoken to or corresponded with hundreds of investigators who have been directly involved in many inquiries. I have spoken to and spent time with airline staff members and regulatory personnel in the air, in boardrooms and workshops.
I have visited regulatory and investigative institutions like the NTSB, the FAA, AAIB, BEA, DCA, CAA and others. I have been privileged to be granted access to the actual recovered or stored wreckage of numerous aircraft that have crashed.
Investigators dealing with these pieces of evidence have demonstrated how they have tracked down the causes of the accidents. Numerous laboratory tests and post-crash simulations as well as various testing rigs developed for specific investigations have been witnessed, visited in-situ or viewed on video..
Aircraft accident investigation is not a black art.
I have gained an in-depth appreciation of the fact that accident investigation is a deliberate, step-by-step process that applies logic and science.
Wherever possible, a standardised approach is used and final reports usually follow a layout as determined by ICAO norms. Anything not present in the wreckage or which is not undisputed evidence is hardly ever included in final reports as fact.
Unsubstantiated rumour is hardly ever speculated upon by investigators. If these rumours are followed-up and cannot yield irrefutable facts to sustain the contentions made, they are discounted and do not appear in the final report.
The visible evidence and the application of science and collective experience of the industry leads, in all but a few cases, to the most logical and likely causes.
As time has passed from the first rough and ready investigations conducted in the early 20th century by one experienced pilot or official to the present, lead investigators around the world have increasingly become versed in multiple disciplines. Their reading on the subjects at hand is extensive and they now have, of course, the benefit of the internet to liaise with colleagues in any country to check aircraft service histories.
Due to the internet age, investigators in the present can call up a catalogue of similar incidents that have occurred to any given airline or aircraft model using Boolean web-searches or by sending an e-mail to any number of peer agencies worldwide .
This was not a tool available to investigators prior to the mid 1990s.
It was certainly not available to the investigators and board members who took on the search for the cause of the loss of flight SA295, the SAA Helderberg.
In the past 25 years worldwide legislation granting access to information that was previously the preserve only of corporate executives or government ministers, has ensured that vital information that sheds light on accidents can now be more readily accessed and exposed. This has made previously reticent manufacturers and officials less able to conceal flaws in products and design.
It has, however, made these same executives no less keen to obfuscate the facts where any hint of corporate liability may be found.
Throughout this period of my research and writing, I believe I have obtained a good overall understanding of the role players in civil aviation and the tremendous economic and political forces at work in the industry. The financial pressures on manufacturers and airlines are massive and the numbers involved in even seemingly insignificant decisions can make your eyes water.
All my books and articles have sought to set out, in plain English, the circumstances of each accident flight. Thereafter I have presented a narrative synopsis of the work undertaken by the authorised investigators of the day. The conclusions of the relevant official reports and the subsequent flight safety recommendations have concluded all chapters in my books.
I did not, at first, feel qualified to draw conclusions on hearsay nor to include as fact anything not present in the evidence or that had not yet been proven beyond a reasonable doubt. This is why my book about SAA accidents explained only the official findings of the relevant boards of inquiry where available.
Where I stepped slightly beyond this self-imposed boundary was with reference to the situation regarding the fire fighting regulations that permitted the Boeing 747 Combi model to be, in reality, an accident waiting to happen.
During my discussions regarding this accident with investigators, legal representatives and others during the early 1990s, I came to realise that there may have been a financial imperative on the manufacturer to ensure that its product was not made the subject of any litigation by the insurers or relatives of the passengers aboard the flight.
As is well known, there remains considerable speculation as to the actual cause of the in-flight fire suffered by flight SA295 in November 1987.
MY JOURNEY TO A RE-APPRAISAL OF THE HELDERBERG ACCIDENT
While researching various international airliner accidents subsequent to 1987 for a book currently being written, I have come across numerous further in-flight fire reports and investigations. The key period that has relevance to this article lies between 1993 and 2012. Many of of these accidents have many material circumstances in their make-up that echo in the SA295 fire.
The catalogue of subsequent changes to regulations and certification criteria regarding aircraft systems and materials to prevent in-flight fires have combined to prompt me to review the circumstances and investigations surrounding flight SA295.
I shall set out the factual aspects of my research herein and place the resources used at the reader's disposal in order that - in my view - the only logical conclusion to be drawn from the facts as they stand on the record, may be validated or rejected.
I do so, however, as I am of the firm view that the facts uncovered in all such in-flight fire incidents to date - as well as the moves by various military arms around the world to remove from their aircraft the combustible materials causing control malfunctions or in-flight fires - point to the fact that the passengers of SA295 were the first casualties of a dangerous combination of circumstances that has claimed further lives since.
The accident took place at night in November 1987, over the Indian Ocean, prior to cell phones, text messages, e-mail or the internet being available to most people.
The last sunstantive communications from the aircraft indicated that the crew had a smoke problem aboard the aircraft and they had initiated an emergency descent as per a checklist relevant to the situation.
Amongst the information about the on-board situation that was later determined are the following facts:
* A number of electrical circuits had tripped and coninued to do so as the emergency developed.
* A fire of high temperature and small area had ignited near the front right of the cargo bay area.
* The fire later developed into one fuelled by packaging materials and cargo. This was not limited only to pallert PR (Front right) but involved the tops of many pallets of cargo.
* The fire damaged items high up in the crown of the fuselage including control cables, pulleys and structural components.
* The fire generated large amounts of toxic smoke.
* The fire weakened the structure and melted through fuselage components essential to the integrity of the airframe.
Nothing further was heard from the aircraft after an acknowledgement of a landing instruction and it was later determined the Helderberg crashed into the sea a few minutes after the last recorded communication.
The Margo Board of Inquiry into SA295
The Board of inquiry was established in terms of the South African Civil Aviation regulations of the day. A large impediment to the satisfactory conclusion of the inquiry was presented in the form of the accident itself and the way the world exchanged information at the time - especially given the scenario in which South Africa found itself at the time - the target of various embargoes and trade sanctions.
Furthermore, the aircraft was the first of its type to experience an in-flight fire. Allegedly, there was no prior art or data on a possible origin for the fire to help guide the investigation in this respect. It was also the first of its type to crash. It crashed in a part of the ocean which was 4 400m in depth. No wreckage of any kind had hitherto been recovered from such depths.
Given the limitations of the technology of the time and the general belligerence of the government of the day - which was the owner of the airline - it would have been expected that they would seek to blame the liberation movements with whom they were engaged in a low-grade civil war for the loss. This would have provided them with a lot of mileage to bolster their propaganda against the movements.
They did not do this.
If, as many seek to prove, they were in some manner guilty of misconduct that led to the accident, the easiest way to cover things would have been to simply shrug it all off as a regrettable tragedy and say "Jammer. It's too deep. We cannot find out what happened. It's just one of those things." and left it at that.
Certainly, if there was any hint of foul play involving the shareholder or operator, that would have been the simplest and most logical thing for them to do. It would certainly have saved large chunks of precious foreign exchange that were used to fund the location and recovery efforts. This was certainly a consideration at a time when it could more profitably have been used to bribe sanctions-busters to further the aims of the then government or state agencies in procuring embargoed items.
Nevertheless, in the event, the investigating authorities and the operator devoted massive funding to locate and recover the wreckage.
As it turned out, the circumstances of the accident prevented a total reconstruction of the aircraft. This was due to the fact that recovery of the majority of the wreckage was simply an impossible task given the depth and fragmentation of the airframe.
This meant that the investigation board could do no more than its best with the minimalistic material to hand at the time to satisfy its primary mandates.
- To determine the cause of the accident and make safety recommendations so as to prevent a recurrence and
- To determine responsibility (if any) for the accident.
THE IN FLIGHT FIRE
It was apparent from evidence - and this fact is not in dispute by any parties to date - that a fire broke out aboard the airliner. As it could not be extinguished, this fire led, in some manner, to the impact of the aircraft with the ocean.
Despite the small amount of the airframe recovered it was felt at the time by the board members that sufficient information had been gathered to determine that:
1. The fire detection and fighting facilities aboard such airliners where woefully inadequate and,
2. The primary reason the aircraft crashed was that a fire developed that could not be detected or effectively doused with the equipment on board at the time.
This was in spite of the fire detection and fighting facilities being "legal" in that they complied with the then state of the art in FAA fire fighting regulations. It was pitifully obvious that they were not nearly as effective as they could have been. In this respect, the basic design was undoubtedly at fault - perhaps not wilfuly so as the exact circumstances involved might not have been considered whent he design was put together.
What was the official cause of the fire?
The board and investigators felt that they had insufficient evidence available upon which to base a determination of the source of ignition leading to the fire.
The board, the chief investigator and the operator all assumed the fire had originated within the cargo itself. The manufacturer's expert's report, despite stating that there was nothing declared in the cargo that could have ignited, also - surprisingly - stated that the fire had started within the cargo.
Furthermore, the expert's report distanced the aircraft manufacturer from any responsibility by flatly stating that the aircraft's wiring system could not possibly have played any role in starting the fire.
I now contend that, given the air accident investigation record in the interim, that this statement regarding the wiring system being faultless must be called into question. It appears to have been a calculated attempt by the manufacturer to divert attention from a potential problem about which they had full knowledge at the time.
So, what did the Margo report say?
The board made recommendations which it felt would adequately prevent a recurrence of a similar accident. They proposed a total ban on mixing passengers and cargo on the same deck as well as the upgrading the fire detection, resistance and dousing capabilities of cargo compartments.
Could they have missed something?
Well, on a reading of their report with the benefit of hindsight, there are one or two unexplained issues that appear to have been glossed-over.
In the Boeing Company's expert and the Board of Inquiry's final reports, these facts were not expanded upon:
- There was evidence of arcing in the wiring looms recovered from the front of the cargo bay area.
- Numerous insulation blankets had detached from their mounting clips.
- Cargo nets had been found with their top sections (over the pallets) burnt away.
- Molten plastic material was noted on the cargo bay floor.
THINGS TO CONSIDER:
a) It was assumed by all parties, given a reading of the testimony to the board, that the arcing of the wires was a result of the fire.
b) In the then state of the art, the insulation blankets were believed to be fire-proof as they had passed the Vertical Bunsen Burner test devised in the mid 1960s. This test passed any material that did not burst into flame after being held a meter above a bunsen burner flame for 20 seconds. (The inadequacy of such a test needs no further elucidation.)
EVIDENCE OF THE DAY REGARDING POSSIBLE SOURCES OF THE FIRE
The board felt it could not, on the available evidence, draw firm conclusions on an ignition source. This was so as not all the items packed in the cargo hold, more especially in pallet PR which was the supposed seat of the fire, could be retrieved and tested.
Many reports and investigations into the fire and the possible effects thereof on the cargo hold were, however, available to the board. These all made use of the general wisdom of the day as regards the fire safety aspects of the materials aboard the aircraft.
MMM...WHAT ABOUT THE BURGOYNE REPORT COMMISSIONED BY BOEING?
A fire expert retained by the manufacturer of the aircraft stated that it was his opinion that the fire had been caused by a self-sustaining material/source in its initial stages and that it later developed into a diffusion fire fuelled by the packaging materials in the front right hand pallet. (See Burgoyne Report in hot links section)
Of particular interest in this report are the following:
- He was convinced that nothing in the aircraft's systems could have started the fire as the manufacturer had told him this was not possible.
- The very early stages of the fire involved high temperatures.
- The initial fuel for the fire was quickly exhausted.
- There is evidence that flames spread upwards from the top of pallet PR in a V or Y shape towards the top of the fuselage.
- The fire did not burn down to the floor level and it was not very large ("about the size of an armchair or small sofa") involving only the upper parts of the pallets and, in particular, pallet PR.
- There was a section of the aircraft wiring on a beam above the partition between the cargo bay and the rear galley that showed evidence of electrical arcing.
- In his view the amount of molten copper material that could have dripped from this wiring was not of a sufficient quantity to have ignited the cargo and cause the ensuing fire.
- The rest of the wiring loom in the cargo bay was not inspected.
- There were numerous globules of molten plastic material on the floor wreckage in the vicinity of pallet PR and behind the area where the 9G barrier net (set in front of the freight to prevent it entering the passenger area) was mounted.
- Many of the insulation blankets had fallen away as their mounting clips had melted.
Mr Southeard, the author of the report, further states that the diffusion fire, which he suspected followed the initial high-energy fire, most likely involved the packaging material within the pallet.
His report further states that he found nothing declared in the cargo that could have ignited and burnt at a high temperature or that could have sustained such a fire.
Despite this declaration, Mr Southeard nevertheless states in his conclusion that the fire originated within pallet PR.
Many of those attempting to solve the puzzle of the fire have seized on the aspects of a "promoted fire in the early stages" and the "within pallet PR" statements to bolster arguments that the promoting agent could only have been some type of undeclared consignment within the cargo itself.
Such a position is not, taken on a reading of the Burgoyne report, unreasonable.
MORE THINGS TO CONSIDER:
a) Mr Southeard's findings are to be assumed as accurate given his stated viewpoint and observations of the evidence presented to, or inspected by him.
b) His statement that nothing within the aircraft's systems could have caused the fire must, however, be regarded with circumspection given that he was retained by the manufacturer and that the manufacturer would be fearful of punitive damages claims in the event of known design or other faults and that it would have sought to deflect any hint of a defect in the aircraft.
c) The manufacture had briefed Mr Southeard prior to his journey to inspect the wreckage. He could not, therefore, have had a totally open mind on certain aspects of the design and construction of the airliner. He would have taken his briefing into account - and he did just that.
d) Neither Mr Southeard nor the manufacturer allegedly had - at the time - extensive intelligence at hand regarding in-flight fires aboard airliners and the causes of same such as has become available in the intervening 26 years.
e) Mr Southeard believed, as did others at the time, that the wiring and insulation blankets he observed and mentioned, were fire-proof.
THE SAA CARGO BAY MOCK-UP TEST
SAA constructed a mock-up of the cargo bay of the airliner in which they conducted a test for the board. The test involved the ignition of cardboard, polystyrene and other packing material within a dimensionally accurate reproduction of the cargo bay.
This test proved:
a) That packaging materials could have burnt quite fiercely
b) The cargo bay volume quickly filled with thick, acrid smoke that would make it almost impossible for anyone to see in the compartment.
SO, WAS THE MOCK FIRE A GOOD EXPERIMENT?
The mock-up was fitted with similar smoke detectors as had been installed aboard SA295. As they quickly went off the mock fire also proved that the alarms would have been triggered within a few minutes. This is also consistent with the information recorded on the CVR.
The mock-up did not. as far as can be confirmed, include the following:
- A complete fuselage section with the airflow simulated to replicate the circumstances aboard the aircraft where the pressure between the passenger area and the cargo bay was supposed to draw air into the cargo bay area. This airflow could have played a role in the initial stages of the fire.
- All the wiring looms in the raceways above the left and right sides of the cargo bay and specifically above or near pallet PR.
- The 115V AC loom that powered the lights in the cargo bay that runs over the life-raft support beam between the cargo bay and the rear galley unit 4B.
- The wiring loom referred to in the Burgoyne Report (Which may have been the same as the 115V one in 3 above.)
- The rear galley unit 4B.
- The insulation blankets attached with nylon clips above the wiring loom against the outer skin of the aircraft.
- Pallets stacked and packed - covered and uncovered - as near as they were aboard SA295.
As such, the simulation could not, by any means, be deemed a replica of the situation aboard the airliner. In that aspect, therefore, it was not helpful in directing the board's attention at possible ignition sources and their effects.
SOME MORE THINGS TO THINK ABOUT:
a) Given the state of the art at the time, the insulation blankets were believed by the airline and the industry at large, to be fire proof.
b) In addition, the wiring systems were believed by the industry - based on representations of the manufacturer - to be durable, fire retardant and non-flammable.
c) No scenario involving burning materials falling on top of the pallet from above was investigated.
SO, WHAT HAS THE INDUSTRY LEARNED SINCE?
In research for my new book, I began investigating the loss of Swissair flight 111 and 23 other incidents in airliners involving in-flight fires.
I have discovered that the FAA and the airliner manufacturers have both embarked on projects to remove the following materials from the world wide airliner fleet because they are known to be highly volatile and fire-starters. The US military had already begun removing the wiring material from its aircraft in the mid to late 1980s.
- Kapton insulated wiring.
- Metalised Mylar and/or AN-26 insulation material.
Both of these materials were aboard the HELDERBERG