Debating the River Plate Battle
Captain Peter G. Hore, Royal Navy (Retired)
I am deeply concerned at the inaccuracies and the language in the article in August’s Naval History about the Battle of the River Plate (“A Battle Badly Fought”).
The author, Dr. Alan Zimm, tells me he is neither an academic nor a historian but an “operational analyst working navy problems.” It is a weakness, therefore, that he takes as his data source a two-penny propaganda leaflet, rather than Battle Summary No. 28: The Chase and Destruction of the Graf Spee, which was circulated in wartime so that the battle might be studied.
Also, the U.S. Navy’s Fire Effect System is conflated with the Royal Navy’s War Game Rules 1929 (C.B. 3011). The latter was not a guide to fighting: The key word is “game.” I know of no occasion when a British naval commander consulted the War Game Rules before or during battle.
The author argues that the British had an advantage in firepower and tonnage. However, tonnage is a spurious comparator when armor is what matters, and the Graf Spee’s armor was proof against the 6-inch shells of British Commodore Henry Harwood’s light cruisers except at point-blank range. Beyond this range, the light cruisers were incapable of inflicting “vital hits” or “speed hits” (as defined in War Game Rules), and the best that Harwood could hope for was to inflict “non-vital hits,” whose cumulative effect would be to degrade the Graf Spee’s fighting capacity.
The author also argues that the British enjoyed greater firepower because their rate of fire (pounds per minute) exceeded the Germans’, but this is like saying that several machine guns are superior to a tank. In any case, this doubtful arithmetic was altered in German favor when the heavy cruiser HMS Exeter was put out of action.
It is untrue that Harwood was timid in wanting to stay outside 15,000-yard range and that he wished to fight at long range. The Graf Spee had a 10,000-yard range advantage in which she could hit Harwood’s ships without risk of return fire, and, anyway, the 1939 Fighting Instructions were explicit in calling for action at short range. Thus, Harwood’s order “attack at once” was to get within close, effective gun range as soon as possible.
Therefore, Harwood split his squadron, turning his light cruisers northward, placing the Graf Spee between them and the Exeter and obliging the Graf Spee to divide the fire of her main battery. When the Graf Spee turned westward, Harwood’s tactical problem changed. He had to reduce the range while bringing his broadsides to bear and to clear the Graf Spee’s smokescreen. He could open “A” arcs only by the occasional turn outward. Only during the exchange of torpedo fire did the light cruisers turn away, but they continued the turn 180 degrees to resume the chase of their foe.
History tells us that Harwood was determined and optimistic during the battle. He was not beset with “cognitive dissonance” after receiving an erroneous report of ammunition consumption, and he would have known that Fighting Instructions stated, “It is unsound . . . to refrain from engaging an enemy in order to husband ammunition.” Even if the state of Harwood’s mind during the battle were not known, the author’s accusations of “confirmation bias,” “status quo bias,” “target fixation,” and “monumental loss of situation awareness” cannot be drawn from operational analysis and are unsubstantiated.
However, when the author writes that Harwood “retreated,” I wonder if he has studied the same events as other scholars over the past 80 years. How can Harwood’s maneuvering of his ships be described as a retreat? The Graf Spee turned west and fled toward neutral waters of the River Plate. Harwood chased and imposed a blockade, signaling to his depleted squadron “My object: destruction.” How can this be described as a retreat?
The battle ended when the Graf Spee scuttled herself. Having accused Harwood of “turn[ing] away from a decisive victory,” and Churchill of manufacturing a great victory, could it be explained how the sight of your enemy aground in the shallows and burning does not constitute a victory?
True, there were no vital or speed hits, but victory had been achieved through the cumulative effect of non-vital hits on the Graf Spee, including the effect on German morale. If in doubt, one should read the sheaves of congratulatory letters to Harwood, including those from the United States.
CAPT Hore’s 38-year career in the Royal Navy included serving as joint logistics commander on Ascension Island during the Falklands War and as head of Defence Studies during Britain’s 1998 Strategic Defence Review. Historian, obituarist, and biographer, his works include Henry Harwood: Hero of the River Plate (Seaforth Publishing, 2018).
Dr. Zimm responds:
Captain Hore contends I took as my data source “a two-penny propaganda leaflet.” I used official data from the U.S. Naval War College (USNWC) and Royal Naval College (RNC) to show that the leaflet distorted the force balance. I didn’t use the leaflet data; I challenged it and showed that historians are wrong in accepting it.
I didn’t conflate the USN’s Fire Effect System with the Royal Navy’s War Game Rules 1929. They were consulted separately. Both independent calculations showed Commodore Henry Harwood’s force was two to five times as powerful as the Graf Spee. These calculations represent official professional judgments developed independently over decades by naval officers, bureaus, and agencies. Both models indicate the Graf Spee should have been destroyed at sea.
I replayed the battle with the USNWC rules. Using the historical tracks and fire distribution the result was within a few percentage points of the historical result, and the Graf Spee survived. Duplicating the historical result lends credence to the model. Another run incorporated better British decisions, and the Graf Spee was destroyed. Results of single combat experiments are not proof, but they do support the contention that Harwood had sufficient force to destroy the Graf Spee and that poor decisions made a critical difference.
The captain writes, “[The War Game Rules] was not a guide to fighting: The key word is ‘game.’” Modern terminology would describe the USNWC Maneuver Rules and Confidential Book 3011 (C.B. 3011) War Game Rules as sophisticated mathematical combat models reflecting official judgment. As early as 1904, the First Sea Lord, Admiral “Jacky” Fisher, maintained a war “gaming” table for developing fleet tactics. Wargaming was added to the Royal Naval College curriculum in 1907, with games played twice a week for training and testing tactics. C.B. 3011 was distributed to the fleet for training. C.B. 3011 was not a toy.
Mathematical gaming models are not designed to be consulted during battle. They contribute to planning and build the mental models informing a commander’s decision-making.
As for the claim “armor is what matters,” the official position of contemporary British and U.S. officers was that non-penetrating hits could destroy an armored target. The USNWC assessed a non-penetrating hit on average as 33 to 50 percent as damaging as a penetrating hit. C.B. 3011 assessed that 24 non-penetrating 6-inch hits would destroy the Graf Spee. Machine-gun bullets bouncing off tanks is an inappropriate analogy. Most of a warship is unarmored. At the First Naval Battle of Guadalcanal, the Japanese battleship Hiei was effectively destroyed by guns that could not penetrate her belt armor.
Did Harwood “retreat”? He had a nine-knot speed advantage, which gave him control over the range. At 0738, his light cruisers were steering south. The Graf Spee was on their starboard beam, to the west heading west. Harwood was crossing the Graf Spee’s stern at 8,000 yards and pounding her. On receiving the inaccurate report of low ammunition, Harwood turned to port, to the east, away from the Graf Spee. He opened the range and ceased fire, ending the battle. The dictionary definition of “retreat” is “an act of moving back or withdrawal.”
The contention that “[i]t is untrue that Harwood was timid in wanting to stay outside 15,000-yard range and that he wished to fight at long range” is belied by the track chart. Harwood remained outside 15,000 yards for 54 minutes of firing, turning away three times to stay outside 15,000 yards to employ concentration fire. Regarding the idea these turns were forced by an “exchange of torpedo fire,” they occurred before T+55. The Graf Spee fired a torpedo at T+59, and the light cruisers fired at T+64 and T+71.
Captain Hore is correct in saying that the biases that might have influenced Harwood’s decision processes are “unsubstantiated.” Biases in historical decision-making can never be proven. But if observed behavior corresponds to the classical symptoms of a bias—if it walks like a duck and quacks like a duck . . .—it certainly is something that should be considered in the evaluation of a historical event, and certainly is a warning for present-day naval commanders.
The conclusion remains supported by the facts: the Graf Spee could have been smashed at sea. Harwood instead turned away at the threshold of decisive victory.
Dr. Zimm, a retired U.S. Navy commander and nuclear power qualified surface warfare officer, served at sea for 14 years. He holds degrees in physics, operations research, and policy analysis and strategic planning, and worked in the Aviation Systems and Advanced Concepts Group at the Johns Hopkins University Applied Physics Laboratory.
Congratulations on the great, but sad, story of tennis star Lieutenant Joe Hunt. After reading it, I was reminded of the terrible parallels in the stories of Lieutenant Hunt and Ensign Nile Kinnick, the 1939 Heisman Trophy winner. When World War II broke out, Kinnick also became a naval aviator and, like Hunt, was killed in a training flight accident. The University of Iowa plays its home football games at Kinnick Stadium.
Bottom Contour Navigation
Vice Admiral James A. Sagerholm, U.S. Navy (Retired)
Reading Lieutenant Commander Cutler’s review of Dag Pike’s The History of Navigation (October, p. 62) brought to mind an incident that occurred during my tour in command of the USS Rhea (MSC(O)-52).
It was ten days before Christmas in December 1956. The ship, a wooden-hulled coastal minesweeper, had been in interim overhaul at Elizabeth City, North Carolina, for repair of damage to the hull from teredo worms (see “Armaments & Innovations,” June), work that had taken a month to complete. We took advantage of the time to also get our World War II–era radar finally to operate, and now we were approaching the sea buoy marking the entrance to the channel leading into Charleston Harbor, our homeport.
Dawn was breaking, with a cloudless sky, and the return from the radar reflector on the sea buoy was bright and clear, range about five miles. As daylight increased, we saw that a large fog bank was becoming visible, obscuring the sea buoy, but the radar was still holding it well, and there were also several radar contacts from ships in the area.
When we were a mile or so from the sea buoy, the radar screen went blank. We could hear the foghorns of the ships as they moved out to sea but could not see them. I took the conn and began a slow figure-eight track while informing MinLant (Mine Warfare Forces, Atlantic) headquarters in Charleston of our situation. MinLant rogered and said the fog was forecast to persist the rest of the day.
We continued in the figure-eight pattern with the fog showing no signs of clearing. As I studied the chart, I noticed that the fathom markings ran in fairly parallel lines along the coast, with the 20-fathom line intersecting the end of the stone breakwater marking the entrance channel. I knew we were north of the entrance but didn’t know precisely where.
I put the executive officer on the fathometer in the pilothouse, immediately below the open bridge, with instructions to report the depth every 30 seconds. I headed the ship toward the shore, steaming at five knots. As we approached the 20-fathom line, I turned to port, running down the line, with all eyes on the bridge straining to see the end of the breakwater. After several minutes, there it was, about 100 yards ahead. I came hard left, then right, then right again, keeping the breakwater in sight to starboard.
Keeping well to the right side of the channel, we proceeded into Charleston Harbor, breaking out of the fog as we neared Fort Sumter.
When I was asked how we had managed to navigate in the fog without radar, I said we used bottom contour navigation, which we had—sort of.