The Testimony and the Reconstruction of the Course

From the moment when the author of this report was inclined to accord a strong probability to the sighting by the submarine H.50 of l’Oiseau Blanc, he was also led to believe the reports of sightings at Dungarvan and Carrigaholt, for which, as we will see further on, the indicated Times are compatible with the probable course and the performance of l’Oiseau Blanc, as well as with the prevailing wind conditions. In fact, if the aircraft had effected an emergency landing on the morning of May 8 in Great Britain or Ireland along the presumed course, it would very probably have been quickly discovered. A landing in the Saint George Channel was, of course, possible, but maritime traffic there was very heavy. The precise information examined elsewhere in the Meteorological Report, and the notes sent by The National Meteorological Library in the correspondence mentioned above, showed that there was not a cloud over southern Ireland, and the visibility was good.

The information whose translation [Direct quote; not retranslated. Ed.] follows was published by The Times on May 9, 1927:

A message was sent out last night from the main French wireless stations describing the machine and its intended itinerary, and requesting ships at sea to report its passage.

One might think that this message, which described the aircraft, would allow all the would-be famous amateurs to claim a sighting. But the course of flight described between France and the west coast of Ireland was the one initially anticipated, almost exclusively over water, and not the one on which the submarine H.50, Dungarvan, Kilrush, and Carrigaholt are found; and which corrresponds in general to the final course planned by Coli (course Nº 4). The newspapers seem not to have printed a single report of a sighting in the vicinity of course Nº 1.

Beyond the position taken by the submarine H.50, the aircraft pursued its course of 300°. The map below gives the approximate line of this course. We see that it passes over or in the vicinity of:

• Weymouth, on the south coast of England
• Dungarvan, near the southeast coast of Ireland
• Kilrush
• Carrigaholt

Let us resume reading from the newspapers of 1927.

La Presse of May 9 reports that the private wireless signalled Nungesser’s aircraft over Ireland. L’Humanité of May 9 speaks of semiofficial information from M. Levasseur of the sighting of the aircraft over Southampton. La Presse of May 10 reports an Irish press release signaling the passage of l’Oiseau Blanc over Ireland. The Times of May 10 notes that information received on the 9th says that the machine was seen over Dungarvin [sic-CPM], Waterford County, at 1030 on Sunday morning. Le Populaire, le Matin, L’Excelsior, and others, published on May 11 information from London dated May 10 about the sighting in Dungarvan. One phrase in Le Populaire says clearly that “planes are rarely seen on this part of the Irish coast.”

Le Havre-Eclair and Le Figaro of May 13 published the text which follows, which came from the General Commission of French Aeronautics who had received these two telegrams from the French Air Attache in London:

First Telegram:

Observations Sunday morning, reported in summer time.

1. Nungesser’s aircraft identified with great certainty by submarine H.50 at 50°29′ N and 1°38′ W, at 0715 hours, altitude 300 meters, course NW;
2. Numerous observations report the passage of a similar aircraft in the vicinity of Exeter between 300 and 600 meters, course NW, about 0815 hours;
3. Testimony in Ireland confirmed by an observation at Lismore (County Clare) about 1000 hours, altitude 1000 meters;
4. No local aircraft having been in the air at these same times and in these same areas, to the knowledge of the English authorities, it appears almost certain that Nungesser left the west coast of Ireland near the mouth of the Shannon at 1100 hours.

Second Telegram:

Dublin Consul telegraphs that the inquiries made by the Irish government establish without possible doubt that Nungesser crossed Ireland from Lismore to Carrigaholt, and was seen for the last time here at around 1100 hours.

The first line of the first telegram is the communiqué from the Admiralty published in The Times, without the reference to the Needles. We saw that it was important to notice the time and the longitude.

La Presse of May 12 indicates that London radio asked any possible witness to the flight to alert the French Embassy. On the final news, information sent from London via Reuter and dated May 11 stated that an airplane was glimpsed around 10 o’clock on Sunday morning over Dungarvan, Waterford County (Ireland). Direction west. French colors seen through a telescope. Then, in this same issue, an article date-lined “London, May 11” begins by noting that there are several indications that l’Oiseau Blanc flew over the south of Ireland, from east to west, between 1010 and 1100, on Sunday. Below is the description of the information which concerns the flight, which we may summarize as follows:

• Dungarvan, near Waterford. Witness Mr. Dunphy, retired naval lieutenant, director of the Clonmel Electronics factory; time 1010; normal flight; course east-west; clearly saw a French airplane (le Matin of May 11 clarifies: recognized the aircraft perfectly) (the Times and the Irish Independent of May 10 report 1030).
• Kilrush (sp. Kilrish). Witness Mr. Glynn, Lloyd’s agent in Kilrush; time 1050; course nearly west; saw an aircraft which he believes to be that of Nungesser (he telephoned to the observatory at Loop Head, at the north point of the mouth of the Shannon, but they did not see the aircraft).
• Carrigaholt (sp. Carrigalholt). Witness The Reverend Father Madden; time 1100; course slightly northwest; saw the aircraft starting out over the Atlantic.

One point of objectivity which the same newspaper did not hesitate to make a little farther on, was that none of the sighting information was confirmed, and that the aircraft could be anywhere.

Le Populaire of May 12 gives the same information (more succinctly) about an overflight of Dungarvan, Kilrush, and Carrigaholt, but reports that several Irishmen saw the tricolored cockade and that the aircraft flew at 250 meters. The paper speaks of a search of the Atlantic. Le Populaire of May 13 retracts that line pursuant to the French Consul in Dublin reporting that the Irish government inquest established that Nungesser had crossed Ireland.

La Presse of May 13 gives pertinent information of witnesses from North America. It is in this issue that we find the British release about visual contact from the submarine H.50 which it discussed at length. We also find the following testimony:

Rodwell (suburb of Weymouth). Witness a woman; time 0900 summer time on May 8; no wheels, no floats, marks under one wing, motor loud [the time is not credible – CPM].

This testimony is published also in Paris-Soir and l’Intransigeant on May 13, with more details.

The series of testimonies above on the flight over Weymouth, Dungarvan, Kilrush, and Carrigaholt was also of course published in English language newspapers. We will take particular note of the short paragraph below from the Irish Independent of May 10 (sent by the French Embassy in Dublin):

Mr. J. Dunphy, retired lieutenant Royal Navy and manager of the Clonmel Electric Works, states while at Dungarvan on Sunday, at 1030, he distinctly saw the French aeroplane travelling on a course about NW. The machine was also seen over Tarbett Kerry.[1]

We also note the article from the May 11 issue of The Irish Times (sent by the French Embassy in Dublin) which details the sightings mentioned above, in addition to the sighting at Cappoquin. About the sightings at Dungarvan, the newspaper correspondent in this town remarks:

It was about 1010 in the morning, while people were going to mass. A gentleman who looked at the aircraft with field glasses declared that he had seen the French flag on the aircraft.

The table below was inserted in the article.

Cappoquin is situated seven kilometers east of Lismore.

Where the Airplane Was Sighted Sunday A.M. Place Time Distance Paris 05.21 Start Le Havre 06.48 120 miles Dungarvan 10.10 520 miles Cappoquin (about) 10.16 530 miles Glin (about) 10.40 610 miles Kilrush 10.50 620 miles Carrigaholt 11.00 630 miles (It was not seen passing over Loop Head, but the White Bird is said to have been sighted off Tralee – exact locality and time not given.)

The letter from the Naval Historical Branch, responding to our question about the submarine H.50, forces us to think about these stories. It tells us that it was normal for Loop Head not to see the aircraft as it passed 4 NM from the station. It adds: “As the correspondent for The Times mentions, airplanes were unusual in this part of Ireland, and it is probable than one was seen at Glin and at Kilrush (not necessarily right over head).”

We must compare this phrase with the information from Le Populaire on May 11. It is also important to note the sightings from Devon described by the witnesses as reported in The Navy and Military Record of May 18, 1927 (photocopy sent by the Naval Historical Branch). They are as follows:

• On a line between Exeter and Topsham; seen by Mr. C.L. Wood, plane at high altitude.
• Between Ide and Alphington: the plane, seen by Colonel Eden and his wife, was flying low in a westerly direction. Color white. The witnesses consider that this was Nungesser’s aircraft [Topsham, Ide, and Alphington are at least 5 km from the center of Exeter. – CPM].
• Okehampton: the plane was seen by a friend of Colonel Eden.
• Harland: The fog rendered the plane only partially visible. It seemed to be flying low.
• Woolsery: several miles from the coast of the St. George Channel.

None of these statements gives a time.

The article suggests that the witnesses could have mistaken one of the RAF aircraft engaged in artillery spotting for maneuvers which were taking place [on a Sunday? – CPM] [in the morning at church time? – PRT] in a camp near Okehampton.

In the same publication we find also the declaration by a woman about a sighting at Rodwell, between Portland and Weymouth. The time indicated for the sighting is unacceptable. But the description given is really very interesting: no wheels, no floats, distinctive marks under one wing, motor loud. This description corresponds very accurately to that of l’Oiseau Blanc. This same publication also reports the H.50’s statement, but does not reproduce the communiqué from the British Admiralty.

Finally, we point out the sighting at Dungarvan at about 1000 hours. The French colors were seen through field glasses. Bear in mind the time, the course of the aircraft, and the fact that aircraft were very rare on this part of the coast, we may think that this was l’Oiseau Blanc – pointing out that paragraph which was presented under the formula: “our correspondent in Waterford cables us.”

We must, however, report the opinion of M. Charles Dollfus in the book Nungesser, Ace of Aces, by M. Marcel Jullian, op.cit., stating that Nungesser and Coli’s aircraft, of an immaculate white and without landing gear, would inevitably have to be seen over England on a Sunday. Let’s remember that the weather was good, though slightly foggy.

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The various accounts analyzed briefly above (even in the absence of those from Irish newspapers received later) seemed to coincide sufficiently to make it desirable to find out if there were still any interesting archives in Ireland. The French Embassy in Dublin was asked for help in the search. On February 8, 1982, the response from the Embassy brought a surprise: a letter from an eyewitness which confirmed, 55 years after the fact, the sighting at which he was present. This was Mr. H.G. Glynn, the son of the Lloyd’s agent in Kilrush whose testimony was mentioned above and reported in most of the papers. The letter was addressed to the Embassy and is dated February 2, 1982. It says that Mr. Glynn thinks that he was the last or almost the last to have seen the aircraft en route to the west, out over the Atlantic, on Sunday May 8, 1927. Mr. Glynn recalls that in 1927 his father was the local representative for Lloyd’s in Kilrush, and that he died in 1941. He indicates that he was informed on the subject of Reverend Father Madden, the witness in Carrigaholt, and that Madden had been dead for 25 years. The main paragraph of his letter is the following:

I was only 8 years old when I saw the ’plane, and would have been with my father. My recollection is that the ’plane was flying fairly high over the River Shannon and went west over Knocknagaroon Hill towards the Atlantic. Knocknagaroon Hill is on the Atlantic coast, 5 or 6 miles south west of Kilkee. The association between that ’plane and Knocknagaroon Hill is very clear in my memory.

If we examine a detailed map, we see that a line connecting Dungarvan and this hill passes about 2 km from Carrigaholt.

Mr. Glynn, in a second letter dated January 19 1983, in which he authorizes us to quote his statement, adds:

I still have a distinct recollection of seeing the aeroplane fly out west over Knocknagaroon Hill. My father was greatly interested in this effort by Capt. Nungesser to fly across the Atlantic, from this side, and the fact that both he and I had seen the ’plane made it a topic of family conversation and interest which lasted for long after the reported loss of the two brave pilots and their aeroplane.[2]

The author found not one interview in the French newspapers of 1927 from which he drew information with the witnesses of Dungarvan, Kilrush, and Carrigaholt. Must we then conclude that the papers did not assign any correspondents to these places to ask questions in the days immediately following the disappearance of l’Oiseau Blanc? Nor the Levasseur Company? This is very astonishing.

The entire case summarized above for the flight over Ireland (despite the fact that the official release which was published in 1927 by the Irish government as some newspapers reported was not found) leads the author of this report to believe very strongly that l’Oiseau Blanc set out over the Atlantic on May 8, heading slightly northwest, at 1000 UT (1100 Irish and French summer time), in the vicinity of Carrigaholt at the mouth of the Shannon. This belief is based in particular on the fact that the ground speed of l’Oiseau Blanc which the line of witnesses leads to appears quite compatible with the probable performance of the machine and the wind conditions the wind met, as the following reports show.

The Evaluation of l’Oiseau Blanc’s Speed

If we keep, as we have proposed to do, the evidence of sightings by the submarine H.50, at Dungarvan, and at Carrigaholt, we get Tables 6 and 7 below (see also map). (For Dungarvan, we use the time indicated in The Times of May 10: 1005, summer time of course, and which is found in an article in the Irish Independent of the same date.) Table 7 recapitulates flight times and duration.

Table 6 Course Distance Duration GS NM Km Kts. Km/hr Etretat-H.50 93 172 57 m 98 181 H.50-Dungarvan 233 432 2 h 20 m 100 185 Dungarvan-Carrigaholt 35 64 55 m 97 179 H.50-Carrigaholt 322 596 3 h 15 m 99 183

Table 7 Place May 8, 1927 Hour of Departure or Sighting (UT) Duration of Segment Total Duration Le Bourget 0418 Etretat 0548 1 h 30 m 1 h 30 m H.50 0645 0 h 57 m 2 h 27 m Dungarvan 0905 2 h 20 m 4 h 47 m Carrigaholt 1000 0 h 55m 5 h 42 m

How did the wind influence this course on the morning of May 8? The meteorology Report says that at Cherbourg at 0300 GMT, the report was of one quarter obscured sky with a weak easterly wind. At 0335 at Cherbourg, winds aloft were east at 14 km/h at 500 meters, east at 36 km/h at 1000 meters.

Recall that at 0800 summer time, one and a quarter hours after the plane passed Etretat, the wind at Havre was ESE at 2 m/s or 7 km/h; at Cherbourg ENE at 2 m/s also; and at Abbeville ENE, 5.9 m/s or 21 km/h. On the British coast, remember that the documentation gives us a wind over the Channel from the ENE at 7-15 knots, occasionally gusting to 20-25 knots. Between Cornwall and southern Ireland, we have a wind from the east at 7-15 knots. The Daily Weather Reports from the weather bureau in London indicate further that at 0700 GMT at Plymouth, the wind was E at 4 Beaufort (20-28 km/h); at Pembroke NE at 4 Beaufort as well; and at Valentia (southeast Ireland) NE at 3 Beaufort (12-19 km/h). The map shows these places. The Report mentions that at 1000 GMT, at Plymouth, wind from the ESE at 5 Beaufort (29-38 km/h) and at Valentia from the E at 4 Beaufort (20-28 km/h).

In view of the preceding facts, we can use as an average between Etretat and the sighting from the H.50 a wind velocity of 25 km/h at 70°. For l’Oiseau Blanc making a course of 300° true with a ground speed of 181 km/h, the calculations lead to an average correct speed at low altitude of 165 km/h. This result seems quite acceptable given the progress of the flight between Le Bourget and Etretat. In a similar manner, we can figure in an easterly wind at about 12 km/h for the portion of the course between H.50 and Carrigaholt, which gives us an average correct speed at low altitude in this section of 173 km/h, which is compatible with the performance expected of l’Oiseau Blanc.

Table 8
No. of Hours	Duration in Hrs Since Takeoff	Horsepower of Indicated Power Settings	Est. Speed in KM/H
2	1	470	—
3	1	455	—
4	1	440	173
5	1.5	425	173
6.5	1.5	400	169
8	2.5	380	166
10.5	2.5	350	164
13	3	320	161
16	5	295	158
21	6	255	154
27	15	215	150

Remember that the “Point d’Interrogation” of Costes and Bellonte, which left from Bourget at 0954, passed Loop Head at 1500. The duration of that leg was 5 hours 6 minutes, while l’Oiseau Blanc did the same leg in 5 hours 46 minutes. The latter therefore had a ground speed which was nearly 88% of that of the “Point d’Interrogation.”

Let us try to make a table (Table 8) of the correct speed of the aircraft at low altitude as a function of the published power settings. We note in passing that the air temperature at ground level was without doubt in the vicinity of 16°C, and the pressure on the order of 1016mb. It is not necessary to state the first two legs’ speed, and we will use the numbers below, the power settings being those set up in the trials described above (Chapter 1).

This table, which we must not treat with more confidence than we can attribute to the elements which form the basis for its conception, is only intended to permit us to determine, on the route which was to be followed by l’Oiseau Blanc over the Atlantic, the possible times of passing of coordinate points along the way. Note also that it is posible that at full power and full load, the aircraft may have attained the 185 km/h announced by Le Populaire of May 15, 1927.

The Course Reversal; The Emergency Land or Sea Landing

In the preceding pages the eventuality of a course reversal by the crew came up. It is important to examine a little more closely the consequences of such a U-turn.

The aircraft had at its disposal a range of about 40 hours of flight on departure from Bourget. At a point over Carrigaholt the aircraft was still capable of remaining in the air for about 34 hours. The practical significance of this is that if the crew had decided to return from out over the Atlantic – on verifying, for example, that the wind was infinitely less favorable than that which was forecast on departure, or that the weather conditions were very dangerous at the time at which he knew the weather of the route he followed and its probable evolution – it would be with an excellent chance of reaching Ireland again on condition that the reversal was performed summarily no later than sunset for them, in the area of 45° (see Chapter 6). Under these conditions, the return flight over Ireland would take place no later than May 9, about 2000 UT.

The technical designs peculiar to the aircraft, and especially the motor, susceptible to leading to a decision to turn around, would very probably have caused a ground or sea landing in a relatively short time. However, we may not completely exclude, for example, an oil leak which caused a slow but inevitable lowering of the quantity available. The return being decided upon, it is completely conceivable that the loss remained constant for some hours, which would greatly increase the chance of a forced landing on land or sea. Willy Coppens from Houthulst, in an article published in Nº 42 of the magazine Icare (1967), recalled that the oil reservoir of the “Spirit of St. Louis” of Lindbergh revealed at Le Bourget “a crack which had to be repaired. By chance this crack occured at altitude …”

During this entire period, between May 8 at 1000 UT and May 9 at 2000 UT, not a single sighting was found in the papers which were consulted. We will note that the overflight could have taken place at night, and on the other hand, that the research which was done was far from exhaustive.

As was noted above, the meteorological conditions which prevailed over the north of France on May 8 and 9 do not appear of such a nature as to render perilous an overflight by l’Oiseau Blanc on the hypothetical course reversal. As for the course out, we may rightly think that if an emergency landing had been made, the aircraft would probably have been found. No search took place on the Saint George Channel. But if there was an emergency sea landing on the Channel, we do not have the same problem as with the course out, for the searches were very certainly not pursued on the day of May 9.

In the hypothesis of a sea landing on the Channel which, in the case of a course reversal, could only have taken place between May 8 at 1400 UT and May 9 at about 2000 UT, the statement of M. Duchemin, saying that his father saw wreckage which he considered to be l’Oiseau Blanc, not on the 8th but on May 9 or 10, appears to be more plausible. But we still have no way of determining whether this wreckage was indeed Nungesser and Coli’s aircraft, or other wreckage, from a ship or example, such as that reported by Admiral Troude or the one from Telen Mor (see above).

It is important to clarify that the possibility of encountering wind or weather conditions over the Atlantic which were generally very unfavorable for the attempt appears very unlikely, at least before the point of no return had been reached. The probability of a course reversal not followed by a quick land or sea landing appears extremely remote. One could read in La Presse and L’Humanité of May 31 a story which had l’Oiseau Blanc crashing 150 miles from Ireland in the Castle-Shannon Bay. The proof cited (a strong odor of fuel) is not very convincing. It is not possible to be any surer about the problem of a course reversal and emergency land or sea landing.

The May 13, 1927 Le Journal published in an unsigned article the report of an interview with the engineer Barbarou from which the following phrases are extracted:

The eminent engineer wished to tell us that all of his interpretations had as their base the passage of the white plane over Ireland. Nungesser and Coli were supposed to cross the area in about five hours after departure, at a minimum altitude of 1000 meters; and if, at the moment pinpointed on their progress tables for direction and altitude, they could see that everything was going according to the mathematical checkpoints established before their departure, they could embark over the Atlantic; but only under these conditions. In case of doubt, the aircraft would immediately have reversed course, in order to land on one of the numerous British rivers. Given that its passage was confirmed by the official telegrams, at the time and the altitude anticipated, all hope is permitted …