Suspicious Aviation Tragedies — November 27 1989 : Avianca Flight 203

“No one acts alone without orders in the FBI. We had clear goals which were clearly given to us in every document we received from anyone. If a police organization wished for us to provide them “proof” of guilt, then they told us in many ways of their absolute belief that the perpetrators were those individuals they had already arrested. If the president of the United States tells the country in the national news that Dandeny Munoz Mosquera is one of the most feared assassins in the history of the world, then every agent knows that he must provide information to support that statement. If leaders decide without concern for foundation of truth then most people will follow them.”

Fred Whitehurst — Former FBI Chemist (Email to the author)

Avianca 203

Avianca Airlines Flight 203 was a Colombian domestic passenger flight from El Dorado International Airport in Bogotá to Alfonso Bonilla Aragón International Airport in Cali. Avianca Flight 203 crashed over the municipality of Soacha on November 27, 1989. Allegedly, the plane was destroyed by a bomb. This explanation is however much disputed by experts today. Follow us on Twitter: @INTEL_TODAY

RELATED POST: Suspicious Aviation Tragedies — Overview

RELATED POST: PT/35(b) — The Most Expensive Forgery in History [Lockerbie]

RELATED POST: NEVER FORGET — Suspicious Aviation Tragedies: 1961 — Ndola United Nations DC-6 crash [UPDATE: UN REPORT Sept 26 2017]

RELATED POST: Suspicious Aviation Tragedies: Aerolinee Itavia Flight 870 (USTICA-1980)

RELATED POST: Suspicious Aviation Tragedies: 1989 — UTA Flight 772 (September 19 1989)

The aircraft took off from the Colombian capital Bogotá en route to Cali. It was in the air for five minutes and flying at a speed of 794 kilometres per hour (493 mph) when — according to the official truth — an explosive charge detonated on board, igniting fuel vapors in an empty fuel tank.

The bombing of Flight 203 was the deadliest single criminal attack in the many decades of Colombian violence.

Pablo Escobar of the Medellín drug cartel planned the bombing, hoping it would kill presidential candidate for the 1990 elections César Gaviria Trujillo.

Gaviria, however, was not on the aircraft, and would go on to become President of Colombia.

Two Americans were among the dead, and because of this, the Bush Administration began Intelligence Support Activity operations to find Escobar.

Dandeny Muñoz Mosquera, the chief assassin for the Medellín Cartel, was convicted of the bombing in a US District Court and was sentenced to 10 consecutive life sentences. [Wikipedia]

Mosquera’s first trial was declared a mistrial. In his second trial, he was convicted on all counts and sentenced to 10 life sentences plus 45 years, all to be served consecutively. He is currently incarcerated at United States Penitentiary, Lee, in Virginia.

While Mosquera was convicted of the Avianca bombing, his involvement in the bombing was questioned by Colombian Attorney General Gustavo de Greiff, who sent a letter to Judge Sterling Johnson before the final trial, stating:

“I felt necessary to inform you…with the intention to avoid the miscarriage of justice in the case you have in your hands. We have no evidence linking Mr. Muñoz Mosquera to that attack.”

The reply was spectacular! De Greiff was accused by United States officials of being involved financially in the cocaine trade. Quite subtle, is it not?

Quotes from witnesses and police

”The plane was flying along when suddenly it exploded, broke in two and fell in flames and smoke,” said a witness, Alfonso Moreno, in an interview with Radio Caracol.

Another witness, Mario Vasquez, said, ”I heard explosions and I thought there was some problem with transformers in the electrical station, but I looked up and saw a plane explode in the air, and bodies and pieces of luggage were falling.”

The director of Colombia’s Civil Aviation Authority, Col. Jorge Gonzalez, said two Colombian Air Force pilots in another plane had reported seeing two explosions aboard the jet.

Investigators found no evidence of a bomb, said Col. Edgar Leal, chief of national police for the state. He said the flight recorder had not been found.

One witness said he saw black smoke pouring from one of the three engines of the plane before it blew up.

A series of scenarios

Over the years, a number of different “confessors” have come forward and claimed to have inside knowledge that a bomb was planted on the flight. These individuals are mostly mafia and ex-mafia members who have offered “information” to aid their own criminal cases.

As these stories have emerged over the years, the “explanation” of Avianca 203 has evolved, changed, and taken on many bizarre features, including the “Gaviria” story, and several other scenarios, such as the alleged use of a tape recorder planted under the seat 15F.

None of these stories is supported by evidence. For example, Gaviria himself has pointed out that in 1989, when he was a presidential candidate, he did not travel on regular commercial flights and never planned to travel on Avianca 203 or any other Avianca flight. And, as explained below, the FBI had no evidence about the location of the alleged bomb and could not even say what kind of explosive (SEMTEX? TNT?) had been used.


On November 28, 2016, the Colombian newspaper El Espectador started publishing an 8 parts investigative report on Flight 203.

The investigative journalists concluded that the explosion was caused by a malfunctioning fuel pump inside a tank, which had been reported several times before.

The articles, written in Spanish, can be found here on the “El Espectador” website. These articles raised several very good points. [I reproduce them as explained by an anonymous expert on the website]

1. There was never a competent and complete accident investigation of Avianca 203. Although the plane fell on land, near the city, much of the debris was never recovered or examined, and left in the field or carried off by thieves. No bomb parts or pieces were recovered, at the crash site, or in subsequent studies of recovered parts.

2. The only “evidence” of a bomb was the opinion of an FBI agent [Rick Hahn], whose opinion was subsequently officially discredited in the FBI “Labgate” scandal which emerged in 1996. The opinion of the FBI agent was based on his physical observation, which lacked any scientific basis, and certain lab results which were obtained in the FBI laboratory which could not, however, rule out the possibility of contamination of the examined samples.

3. It is impossible to say how many people were aboard the flight or who they were.

4. There was a history of mechanical problems with the 727 aircraft which exploded. A circuit breaker serving the right wing boost fuel pump had ripped ten times in the two months before the accident, and been reset by Avianca maintenance personnel without the discovery of any cause of the breaker trip.

In the other Boeing aircraft fuel system explosions, the fuel pumps and the wiring serving the fuel pumps were found to be the likely causes of the explosions.

All eight of the fuel tank boost pumps were removed from the Avianca crash scene by unknown persons, and therefore could not be examined. Therefore, it is very difficult to rule out a similar fuel system cause for the explosion of Avianca 203 based on the available remaining evidence. [You may want to read again the witnesses’ statements at this point…]

Known catastrophic fuel system explosions

Beside quite possibly Avianca 203, there have been at least five known catastrophic fuel system explosions in Boeing transport aircraft. They are:

Southern Air, 1967, Taiwan, Boeing 727, exploded while parked

Philippine Air, Flight 143, 5-11-90, Boeing 737, exploded while parked

TWA 800m 7-17-96, Boeing 747, exploded in flight

Thai Airways Flight 114, 3-3-01, Boeing 737, exploded while parked

Transmile Airlines, 5-5-06, Bangalore India, Boeing 727, exploded while parked.

About the FBI “Labgate”

The US attorney general has accused former FBI Tom Thurman of having altered lab reports in a way that rendered subsequent prosecutions all but impossible. He has been transferred out the FBI forensic laboratory.

“He’s very aggressive, but I think he made some mistakes that needed to be brought to the attention of FBI management,” says Frederic Whitehurst, a former FBI chemist who filed the complaints that led to the inspector general’s report.

“We’re not necessarily going to get the truth out of what we’re doing here,” concluded Whitehurst who now works as an attorney at law and forensic consultant.

The story shed some light on his formation. The report says:

“Williams and Thurman merit special censure for their work. It recommends that Thurman, who has a degree in political science, be reassigned outside the lab and that only scientists work in its explosives section.”

Dr. Whitehurst has authored something like 257 memos to the FBI and Justice Department with various complaints of incompetence, “fabrication of evidence” and perjury of various examiners in the FBI Laboratory (primarily Explosives Unit examiners).

In the world of Forensic Sciences, former FBI William Tobin is a legend. To name but a few of his achievements, Tobin demonstrated, along with his NTSB colleagues, that TWA 800 had been destroyed by mechanical failure at the time when virtually the rest of the world strongly believed a terror act. Both the NTSB and the CIA subsequently presented compelling evidence demonstrating the scientific validity of Tobin’s conclusion.

After retiring, Tobin demonstrated that the Lead content bullet identification technique, used by the FBI for more than four decades, was flawed. Tobin was not allowed to work on this matter while at the FBI.

Tobin knows a few things about superhero Thomas Thurman. Tobin told me that, in his opinion, Thurman and other Explosives Unit examiners were prone to confirmation bias.

Tobin’s opinion is based on “numerous interactions whereby Thurman and other examiners rendered conclusions supporting the prevailing investigative or prosecutorial theory but which were unsupported by scientific fact.

“It was not uncommon to determine that items characterized as ‘chrome-plated’ were nickel-plated, ‘extrusions’ turned out to be drawn products, ‘castings’ turned out to be forgings, white residues characterized as explosive residue turned out to be corrosion products (generally Al2O3 or a non-stoichiometric form), bent nails claimed to be indicative of an explosion, and a truck axle was characterized as having fractured from an explosion (a conclusion rendered solely from an 8-1/2″ x 11″ photograph where the axle was a small fraction of the field of view and the fracture surface itself was not observable). ”

“I put no credence into any scientific or technical conclusions rendered by anyone without a suitable scientific background for that matter, until I can make an independent evaluation. Thurman was a history or political science major to my recollection.”

“It is also apparent that Thurman was very prone to confirmation bias, an observer bias whereby an examiner will tend to see what he is expected to see.

Thurman was a history or political science major to my recollection. His habit, as with most Explosives Unit examiners with whom I interacted and based on numerous court transcript reviews and ‘bailout’ requests I received on several occasions (to ‘bail out’ an examiner who not only misrepresented an item of evidence but also was confronted with more accurate representations of the evidence in trial), was to seek someone else’s expertise and then present it as his own in a courtroom without attribution.

He would frequently come into my office, ask for a ‘quick’ assessment of something (but I would always indicate that my opinion was only a preliminary evaluation and that I would need to conduct proper scientific testing of the item(s)), then weeks later I would see the assessment in a formal FBI Laboratory report to the contributor (of the evidence) as his own ‘scientific’ conclusion,” Tobin added.

Former FBI Rick Hahn was the lead investigator in the Avianca 203 case. During the “Labgate” investigation, Hahn admitted that he was not able to back up any of his “conclusions” about the bombing of Avianca 203; not even the alleged position of the bomb.

According to an expert I interviewed,  the so-called ‘bomb evidence’ reported by Hahn was probably more properly characterized as cratering, not pitting, which is typically a corrosion phenomenon.

When asked if he had any knowledge whatsoever about corrosion mechanisms of aluminum alloys, or had ever seen Al2O3, Hahn admitted that he didn’t have a clue! There is no doubt that Hahn had been “Thurman-trained”.

Comment: Remember that both Thurman and Hahn played a key role in the Lockerbie investigation and that Thurman is credited for solving both the Pan AM 103 (Lockerbie) and the UTA Flight 772 cases. Frightening, is it not?

Preliminary Conclusion

It is very likely that Avianca 203 was not destroyed by a bomb but rather by a fuel system explosion of the type that destroyed at least five other Boeing aircraft.

This issue was very well know but largely ignored by the Avianca engineers despite the fact that the problem had led to numerous Airworthiness Directives by the FAA, which ended with the mandatory installation of “nitrogen inerting systems” in the fuel tanks of 727 and 737 aircraft.

This post will be updated whenever new information is available. Stay tuned!

Avianca Flight 203-Explosión Avianca HK 1803, vuelo 203 20 años RCN TV 13



All 107 Aboard Killed as Colombian Jet Explodes — NYT

Drug Trafficker Convicted Of Blowing Up Jetliner –

The Hit Man Nobody Knows — Westword

Avianca 203 – Why Was It Not Stopped? – … index.html


Suspicious Aviation Tragedies — November 27 1989 : Avianca Flight 203

This entry was posted in Aviation Disasters and tagged , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s