Cruiser Surigao, Luzon Strait, Sunday, 20 September 1942, 0755 Hours Local
Jorge Robles, seconded from the Armada de Chile to teach the principles of dradis operation to personnel of the Philippine Navy, had been working non-stop for months now; as new ships emerged from Philippine shipyards, their crews needed hands-on instruction in the new electronic equipment. The cruiser Surigao was a step up from the Pinatubo-class destroyers he had previously worked aboard – a fine ship for a small light cruiser – and her dradis installation more extensive.
“Senor Robles,” called the student manning the dradis unit. “I have an air contact, I think.”
“That’s odd,” thought Robles. “Let me see,” he said as he stood to look over the student’s shoulder to gaze at the signal autoplot scope. There was no doubt, there was an air contact.
“Notify the bridge,” Robles suggested, “tell them we have an unknown contact. Let’s begin tracking this – it will be a great test of your skills.”
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They tracked the contact for five minutes – it was coming towards them from the north-northwestt, flying at four to five thousand meters.
Captain Alejandro Borromeo came down to the dradis station personally to check the situation. “Senor Robles,” he began, “you are certain of this contact?”
“Sir,” the Chilean replied. “The equipment is functioning normally. We’ve tracked the contact for several minutes – it appears to be a single aircraft, at altitude, heading south.”
Borromeo knew that the Chilean magic box could tell him much but…
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Borromeo considered his options while he returned to the bridge. As far as he knew, there were no commercial flights in this area – and certainly none approaching from the northwest. The air strips on the Batan Islands were not yet operational. Could it be a patrolling PBY? He had his doubts.
“Take a signal for Commander, Northern Fleet; copy to Commander, Northern Sea Frontier. Dradis contact with unknown aircraft approaching from northwest, estimated course 170, estimated height four thousand meters. Give them our position, course and speed.”
The message was quickly radioed to naval headquarters in Cavite, where its receipt caused some consternation and confusion.