Solve the Mystery of STENDEC
Posted February 2, 2001
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The Morse code word STENDEC is an abbreviation for "Stardust Emergency Descent"!
ST=Stardust EN=Emergency DEC=Descent
The aircraft could have stalled in the jet stream due to fuel-air mixture inconsistencies or even icing. The aircrew frantically and hastily sent a Morse message in abbreviated format "STENDEC." Upon emergency descent, the engines powered up again, but it was too late. The engines had just picked up substantial power again, when it slammed into the mountain at full power. There was also probably very little visibility due to cloud cover.
Aviation ordnanceman Jeffrey L. Noble
United States Navy
In communicating Stardust's arrival time, the operator would not have included 'hrs' in the transmission. This has been added by subsequent authors for clarification purposes only.
The text of the message (without pauses) was likely:
Inserting the pauses, which depend on the 'fist' of the operator and may have been misunderstood by the listener, gives us:
The meaning of the transmission seems clear to me:
ETA = estimated time of arrival
SANTIAGO = destination
1745ST = 5.45PM Standard Time (as opposed to Daylight Savings) since August is winter in Chile
END = switching to radio (voice)
EC = misread of AR = End transmission
Your mystery regarding STENDEC is not a mystery at all. It is standard radiotelephony (Morse in 1947). I am a retired senior manager with the Federal Aviation Administration (Air Traffic Control). Many years before my career with the FAA, I was an Instructor Pilot with the United States Airforce. Years before that I was trained in Instrument Flight Rules flight by an old Army Air Corps Flight Instructor, who was 85 years old when he taught me and had taught and flown in Britian during WWII. His pilot's license was signed by Wilbur Wright, the first Administrator of the C.A.A. (the predecessor of the FAA). He knew everything there was to know about flying and aviation, and I valued my time with him. I learned things about aviation from this man that I have never heard anywhere else, before or since. These "jewels of knowledge" have remained with me 'till this day.
S.T.E.N.D.E.C. is purely British. In American Radio Telephony, the equivalent term is: B.O.D., "Beginning of Descent." In British Radio Telephony it's: "STARTING ENROUTE DESCENT" (S.T.E.N.D.E.C.). As soon as I heard this during the broadcast of your program, I recognized it immediately. I am rather surprised that a British aviator hasn't come forward with an explanation of this. Perhaps it hasn't been exposed to a British aviator of the period.
Aviation is sprinkled with acronyms. Many of these acronyms can be very obscure, until you associate yourself with those in the business. Many aviators engaged in the business today aren't even familiar with many of these "older" terms that were in use before modern radio navigation aids and radios. I also began to learn the control of air traffic, with some of these old acronyms. These acronyms mentioned above were quite common in the days when I learned to fly. I still have aviation charts that would have been current when Stardust went down. Things were vastly different in aviation in those days.
I found the following theory in a USENET posting that follows the V and AR theories previously described with a small modification. Instead of the "V" theory for calling attention to the transmission, the first sequence could in fact be the standard Morse prosign "BT" meaning pause or break. This would yield:
"ETA SANTIAGO 1745 HRS BT END AR"
by which the operator meant essentially:
ETA SANTIAGO 1745 HRS
END (end Morse code and go to voice)
(end of message)
The only stipulation is that a leading "-" making the leading S a B must have been missed each time due to the speed of the code, blurring, or bad reception. And although I'm unfamiliar with real Morse code communication, this seems to be more plausible than "V END AR" described previously. Additionally, since the prosigns are supposedly sent without actual breaks between the "letters," it would seem very plausible that the Santiago operator simply misinterpreted the prosign "run-on" combinations as two different letters that would differ only in spaces between characters. For example, "SOS" is not sent as S then O then S, but the continuous sequence "ditditditdahdahdahditditdit" rather than "ditditdit dahdahdah ditditdit". (You must think that I'm loosing my mind ;-)
What's still very odd to me is that both the BT and AR prosigns are apparently very common in Morse CW communication. How could the Santiago operator not have recognized these common patterns immediately?
As a sailor, I am somewhat familiar with acronyms, Morse transmissions, and moments of panic. The following represents one possibility of how the transmission STENDEC may have been missent. Note that the "N" is only slightly different from the "M" (dash-dot vs. dash-dash). When the "N" is replaced by the "M", it becomes STEMDEC, which could be STart EMergency DEsCent. A radio operator in a moment of panic can very easily make an error by cutting the dash a little short in attempting to transmit a message rapidly. Admittedly, he should have used correct codes and procedures and/or corrected it on the second or third transmission, and one will probably never know for sure, but it is a theory worth evaluation. Thanks for listening.
Big Lake, Texas
I have another theory on STENDEC. The radio operator, assuming that they were just a few minutes away from landing, sent his ETA and then STENDEC..... Which was really STRD OUT ..... in CW, RD could have been interpreted as END and AR overscored is the CW for OUT, which could have been interpreted as EC. What he was saying in the long term was "STARDUST OUT." I was a U.S. Air Force airborne radio operator in the early 1950s flying on KC-97 Air Refueling tankers. We used a lot of abbreviations in CW. I believe he was assuming the flight was about to land and he was ending his contact for that flight.
My thought after viewing the NOVA program regarding the Stardust mystery was that the message was an attempt to deliver the most information describing the situation in the least amount of time. This is what I came up with.
This just seems right to me, describing a failure of one of the starboard (or right) engines with a resulting Descent of the aircraft. This theory may also explain why the plane was found about 50 miles off course, as the thrust would be unequal causing possible directional problems. If this code breakdown is correct it was an amazing effort to get the potentially life-saving information out given a limited timeframe. This theory may be proven when the starboard engines are recovered, as the prop damage should verify that one of the right engines was not running at the time of the crash.
Viewer Gary Honas has the best fitting theory so far. V END AR ("Attention! End [of transmission]. Signing off") has precisely the same dot/dash sequence as STENDEC—but with different spacing. Given the speed in which it was sent, Stardust's radio operator and/or the Santiago operator could easily get the spacing slightly off. V END AR, sent rapidly, makes sense when one remembers the crew thought they were only minutes away from landing and had yet to contact Tower to recieve airport information and clearance to land.
Stardust's radio operator needed to switch over to voice as soon as possible, hence, "Attention! End [of transmission]. Signing off". When the Santiago radio operator didn't understand it, Stardust's radio operator simply repeated himself twice. Since his message made sense to him, he figured it should also make sense to Santiago, especially if repeated (simple though erroneous human thinking). The spacing could be slightly off if the aircraft was going through the clouds and being buffetted in the process. Did anyone ever query the Santiago radio operator as to whether he was even familiar with V (as in Attention), and AR (for signing off), or considered these as possiblilities? Would be nice to see the original accident file.
Some of the other theories don't hold water. In aviation, one never says the "engine stalled", as one viewer suggested. We would say "the engine failed, or "has lost power" or similar. STAR—Standard Terminal Arrival Route—is a procedure only 25-30 years old, so that one is out. No one says "Standard Eastern Time", as another viewer guessed; it's Eastern Standard Time. In any case, Greenwich Mean Time (GMT or "Zulu Time") is the standard used in aviation. Other viewers have too vivid an imagination and have played too many games of Scrabble, I fear. One can derive almost anything from such letter-to-word extrapolation. A good principle of science is to be parsimonious—simple explanations are usually closest to reality.
Stefan A. Bailis
Flight engineer/Turbo-jet, reciprocating engine
Former first officer, flight engineer, DC-6, DC-7, Constellation
(large 4-engine transports, only a few years newer than the Lancastrian).
STANDBY is fairly close to STENDEC, perhaps they were telling Control to wait while the figured out where they were.
S ... T - E . N -. D -.. E . C -.-.
S ... T - A .- N -. D -.. B -... Y-.--
Andrew B. Ballantine
I suspect that, just as strange or unexpected things happen, this end-word was a joke being played by the radio officer, DB Harmer, on the receiving individual. It would be interesting to see some inquiry into the psychology of Mr. Harmer regarding any propensity for such acts, and inquiry into any relationship with the receiving individual which might indicate an attempt to be joking or playful. This explanation is as plausible as any offered, more so to my mind.
The first time the message was sent errors occurred. Seconds later, about to crash, the operator panicked and sent the same message. In other words, his reflexes took over. When you're about to die, you dont think about typing words, you pray. He, or should I say his body reflexes, took control and the same message was sent again. No aliens, no mystery, just human nature.
Two more possibilities for the STENDEC message:
Have fun with these options!
- Respacing the characters for STEN (... / - / . / -.), we get VR (...- /.-.) Could the operator have been sending VR DEC or "Visual (flight) Rules, Descent" thinking he was about to break cloud cover over Santiago airport?
- (And this one is a bit far out) Respacing just about all characters, you could get part of "Left Turn" as follows: (missing L) / . / ..-. / - / (extra dit) / - / (D missent instead of U, that is -.. instead of ..-) / .-./ -. possibly indicating a left turn into Santiago airport (reasonable bearing in mind the flight plan.) I have no explanation for the missing letter L - if the Chilean operator thought he had sent "ETA" before STENDEC, then possibly the .-.. (letter L) could have been misread as . / - / .- but that still doesn't explain the repeats of STENDEC when queried by the Chilean.
Keith Ballinger (amateur operator VA3QF)
PS....excellent program >>> ...- / .-
The radio operator in Santiago said that the STENDEC message came quickly from the Stardust all three times. The Stardust was most likely enduring turbulence due either to the jet stream or the weather they were descending into. Would the turbulence affect the morse operator's dexterity?
Stardust's radio operator was named HARMER, which in Morse is very simliar to STENDEC. In fact, it has the exact number of dots and dashes, 15 in each. If the T in STENDEC was mistaken as a dash instead of a dot, the beginning of HARMER is formed by the first five letters in STENDEC. This theory is a real leap, though. There would have had to have been mistakes made at the beginning of the word and the end. At the end of the Morse for HARMER is the same .-. that ends STENDEC. But why would a radio operator end a signal with his name even if these mistakes were plausible?
As a regular user of Morse code on the air I can't shed any light on what the operator was trying to convey with the word STENDEC, but I have an idea why he sent it three times.
I believe Mr. Harmer probably sent his message at a speed that was giving the ground operator some trouble. Thus his comment on speed. In his haste, Mr. Harmer either made a mistake in sending, or the ground operator misunderstood and copied the word STENDEC. The ground operator then queried with STENDEC. (Most professional operators didn't use any punctuation, such as, in this case, a question mark.) Mr. Harmer then copied STENDEC and had no clue what the ground operator was asking, so he responded STENDEC STENDEC (with the question mark implicit). It is not unusual at all to hear this kind of exchange on ham radio. The exchange QTH AGN AGN translates to "your location again again." The actual meaning is "I missed your location the first time, please send it to me two more times.
This is a very interesting topic. I look forward to reading others' theories.
In my opinion, the word "STENDEC" could be caused by a confusion between the English Morse code alphabet and the Spanish Morse code alphabet. After a small investigation of my own, I've determined that the last three letters "dec" could have been confused with the word "gun", which would make "STENDEC" into "STENGUN". At the time, England was involved with Palestine and the repatriation of the Jews to Israel. There was a King's messenger and an individual of Middle Eastern descent on the Stardust.
At the time, very little concern was given to security and a stengun, being a collapsible sub-machine gun, used by British paratroopers, and found in great numbers in the Middle East at the end of World War II, could easily have been smuggled aboard in a small carry-on bag. Both pilots being military veterans, would have recognized the weapon and called it by name. Being an amateur military historian, I have heard this weapon referred to as a "sten".
If in fact the last three letters "dec" were confused with the standard end-of-message letters, they might have been trying to convey the message that someone was on the aircraft, with a weapon, forcing them to do his bidding. The radio operator may have been able to send this message clandestinely, knowing he had to keep it short. But it might have been too late. There could have been a struggle in the cabin, which precipitated the crash. Of course, the true facts will never be known unless the weapon turns up in the wreckage as it emerges from the glacier.
Thank you very much for your consideration.
William E. Hinton, IV
US Army, Ret.
I believe that STENDEC meant: Stardust in Descent or Stardust in Distress. This is what I believe that the aircraft was trying to convey to the tower. My name is Dylan Scott Jones and I am ten years old and was fascinated with the show. Thank you for reading my theory.
Dylan Scott Jones
Palm Desert, CA
As a "HAM" radio operator who is not practiced in Morse code, I believe I have an answer to the enigmatic "STENDEC" message.
First, group the morse characters in the order of the perceived
"... _ . _. _.. . _._." (The spaces between characters are three "dits" or "dots" in layman's terms...)
Now, imagine that you are sending a hurried message, and that the spaces are "blurred" or "non-standard" because of your haste. It might be perceived that you are sending:
"..._ . _._. _ (.._) ._._"
The parenthetical character is a "U," but a hurried "O" (---) might be sent as a "U:" .._
The word then, in English, would be "VECTOR"—a plea for direction.
If English was the language of the skies for these fliers, I believe that static, haste, and perception error translated "VECTOR" into "STENDEC."
To me the message looks very easy. If the pilot really expected to be landing in four minutes, he sent the ETA, time, and then his expected position. In this case, that would be South of the airport by TEN miles and DEsCending. I think he was really lost.
Cedar Rapids, IA
The series of letters "STENDEC" were probably sent correctly since the operator repeated them three times.
"ST" likely abbreviation of STill;
"E" and "N" are coordinates;
"DE" is "FROM" in international Morse from the French word "De" meaning of or from; and
"C" probably means Chile or the Santiago airport.
The letter "N" is also commonly used as an abbreviation of the number "9" in Morse.
Putting the letters together I came up with three possible meanings:
"STill East Nine(nautical miles) DE(from) Chile"
"STill East North "East" of Chile"
or if the operator was unsure of his exact position:
"STill East "or" North of Chile"
P.S. To learn more about Morse code and amateur radio and how to become a "Ham" radio operator, visit the ARRL Web site.
Having watched tonight's program about the unfortunate Stardust crash, my theory about the Morse code message is that the Santiago operator misinterpeted the dashes and dots. I believe the plane radio was sending the signal for U / R / G / E / N / T or ..-/ .-./ --. / . / -. / -
The only difference between STENDEC and URGENT would be two dots, one at the begining and one at the end, which could easily be explained by the sheer terror of the plane operator upon realizing they were headed right into the side of the mountain. If my theory is correct, I would only ask that I would be acknowledged for solving this puzzling mystery and not have someone else plagarize my idea.=
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