WRAL WeatherCenter Blog

Did military forecasters avert disaster for Apollo 11 mission?

Posted July 24, 2019 1:27 p.m. EDT
Updated July 24, 2019 1:28 p.m. EDT

Violent "Screaming Eagle" storms are labeled on this image. (Photo: via US Air Force)

The Apollo 11 mission ended July 24, 1969 at 12:50 pm EDT (6:50 am Hawaii time) with the successful splashdown of the Command Module (CM) Columbia in the Pacific Ocean, 965 miles west southwest of Hawaii.

Results might have been very different if not for two military meteorologists who risked their careers to convince NASA and the Navy to reroute Apollo 11's path home.

Three days earlier, as Neil Armstrong and Buzz Aldrin were walking on the Moon, Air Force Captain Hank Brandli spotted a dangerous storm while reviewing satellite photos at Hickam Air Force Base in Hawaii.

Brandli, a weather tracking and prediction specialist described "violent thunderstorm weather patterns: high-level vortexes that were bird-like, almost an eagle shape. We dubbed them Screaming Eagles,” he said,

The violent thunderstorm with destructive high-altitude winds were heading right for the planned recovery area. NASA needed to be warned but the images were from the highly classified Defense Meteorological Satellite Program (DMSP).

DMSP supported military operations in Vietnam and during the Cuban Missile Crisis. It also supported the top secret Corona program, the first reconnaissance imaging satellite.

Between 1960 and 1972, more than 100 Corona satellites photographed strategic areas in the Soviet Union and China on high resolution film specially designed by Kodak. Film canisters were ejected, reentered the atmosphere and were snagged in midair by Air Force C-119 crews, dubbed the Star Catchers.

Missed canisters (and there weren't many, the Star Catchers were proud of their 87 percent success rate) were retrieved up by the Navy. DSMP cloud cover images helped plan effective use of that limited film and successful retrieval over the Pacific.

"The [storm] would have ripped [Apollo 11's] parachutes to shreds." Brandli described in a 2004 Aviation Week and Space Technology interview. "They’d have crashed into the ocean with a force that would have killed them instantly. I was the only person who knew this and, because the program and its technology were strictly classified, I couldn’t warn NASA.”

Brandli reached out to the Navy's Pearl Harbor office responsible for forecasting weather at the splashdown site.

Navy Captain Willard (Sam) Houston, Jr., who had assumed command of the Fleet Weather Center just days before, agreed to meet in a parking lot on base. Captain Houston, the only Navy officer to work with the Corona program, fortunately still had the top secret clearance necessary to view DMSP photos.

It was now up to Houston alone to convince the Navy to reroute the carrier task group already underway to the planned location, and NASA to reprogram the entry point "without the photos, which were from a satellite that wasn’t supposed to exist.”

To get the carriers to a new splashdown site in time, Rear Admiral Donald Davis, commander of the task force charged with retrieving Apollo 11’s re-entry capsule, had to reroute the entire task force before receiving official orders. "You'd better be right, young man!" Admiral Davis told Houston. Houston described how much he admired "the courage of the decision maker who, acting on the advice of a weatherman, made a decision that was professionally risky, but necessary,” in a 2009 Navy Postgraduate School interview.

Houston then had to convince NASA that civilian weather data wasn't providing the complete picture, again without revealing how he knew what he knew. "I called the satellite program headquarters on their inside line, to convince them they had to get NASA's top meteorologist to make this a national emergency," he recalled.

Apollo 11 splashed down less than 2 miles from the center of the relocated target ellipse. NOAA’s Space meteorology group recorded beautiful weather at the recovery site with visibility of 10 nautical miles, broken clouds at 1,500 feet and a temperature of 82 degrees. The astronauts and their 48 pounds of Moon rocks were onboard the USS Hornet about an hour later and visiting with President Nixon who had arrived aboard the Hornet that morning to welcome the returning heroes.

Brandli and Houston kept their secret until the Corona program was declassified in 1995. They also learned that reconnaissance planes were sent to the original splashdown coordinates that morning where a "screaming eagle" was found tearing through the area just as predicted.

"It still gives me chills to think of what that perfect inspiring mission, the astronauts have come home and died at the very last second. The whole course of space exploration might have been changed completely." said NC State astrophysicist Dr. Katie Mack, recalling hearing as a teenager, from her grandfather how he earned a Navy Commendation for his role in saving Apollo 11. "He told the story to his family but he never exploited it at all in his career" she recalled in a recent Australian Broadcasting Corporation interview.

Mack would go on to attend Caltech, like her grandfather who she idolized. She would also go on to apply to NASA's astronaut program. Mack visited her Grandfather one last time before his death in 2012, sharing the news that she'd made the first cut in NASA's astronaut selection program. "My grandfather was a true science hero" she added. 

Brandli retired from the USAF as a Lt. Colonel in 1976, wrote Air Force's first book on Satellite Meteorology and wrote hundreds of technical articles on the subject before his death in 2009.