Training for the Doolittle Raid on Tokyo
After completing the first modifications to the 24 B-25s that would be used for the raid, the 17th Bomb Group would be transferred to Eglin Field in Valparaiso, Florida. Six crews from each of the 4 squadrons, along with the needed mechanics and support staff would arrive at Eglin with their modified B-25s from February 27th through March 3rd. Eglin Field was a relatively remote base in the panhandle of Florida. The close proximity of the ocean would allow for navigation training over water. It was here that training for the raid, as well as further modifications would happen.
On March 3, 1942, the 17th Bomb Group would meet then Lt. Col. Jimmy Doolittle. Although Lt. Col. Doolittle could not tell them the nature of the mission, he did make it quite clear that the mission would be extremely dangerous and only volunteers would continue. He continued to express that at any time, any one could drop out of the mission without any questions or negative marks. The mission was to be of the upmost secret nature. At no time was any person involved to discuss or disclose what they were doing at Eglin. Up until that point, the crews were set by flight. At Eglin, Lt. Col. Doolittle assigned crews to planes.
Another addition to the group was Lt. Henry L. Miller USN. Lieutenant "Hank" Miller was a naval instructor from nearby Pensacola, Florida. His arrival on March 1, 1942 was met with some skepticism from the 17th. He was to teach the Army crews how to do carrier takeoffs as well as Navy etiquette. At that point, the group had not been told their mission would involve a carrier takeoff. Many in the group were not convinced that a B-25 could indeed be launched from a carrier. The fact that Lt. Miller had never seen a B-25 until arrival at Eglin did not offer any comfort. Lieutenant Miller climbed into the co-pilot seat of a B-25 and Capt. York took the controls. Following standard naval procedure, the B-25 took to the sky in less than half the usual airspeed. Lt. Miller quickly gained their respect.
Training
Pilots and co-pilots focused on short field takeoffs. One runway was painted to simulate a carrier deck. Flags were placed as markers with an initial goal of being airborne before 800 feet. Within a week of practice, everyone was consistently in the air by 400 feet. It became a game with the group. The winner would be Lt. Donald Smith, who was able to get his B-25 airborne in 287 feet. Even Lt. Col. Doolittle took advantage of the naval instructor and also became proficient at getting a B-25 airborne in under 400 feet.
Navigators were challenged as well. Speed tests were run over known distances to calibrate the airspeed indicators. The magnetic compass of each B-25 was also precisely calibrated. The navigators were trained in celestial navigation with sextants. Training flights were flown at sea. Long practice flights from Eglin to Ft Myers to Houston and back were done at night using different methods. The navigators would enjoy some of the most accurate equipment and intense training for the raid.
Bombardier training was equally as challenging. Although the crew still did not know specifics of the mission, they would practice low altitude bomb runs. Bomb runs would typically consist of dropping concrete and sand-loaded practice bombs over an area now known as Fred Gannon state park. Each B-25 was equipped with the state-of-the-art Norden bombsight. Although the bombsight was highly accurate at altitude, it was rendered useless in the high-speed, low level runs practiced. Lieutenant Ross Greening would design a simple solution using 2 pieces of aluminum. The "Mark Twain" bombsight was found to be very effective.
One of the biggest initial concerns was the state of the machine guns in the B-25s. Due to a shortage of ammunition, most of the guns had never been fired. Some jammed after a few rounds and others didn't fire at all. The turrets themselves were a problem as well. They were electrically operated and slow to respond. The lower turret was so difficult to operate it was said that "A man could learn to play the violin well enough for Carnegie Hall before he could learn to fire that thing." Firing the guns close to the fuselage would pop rivets and damage the bomber. All of these issues would be resolved, but the solutions took time. Although the men would practice with .50 caliber machines on the ground, very few would ever fire a shot from the air. Bombardiers would be cross trained as nose gunners and the engineers would also train as turret gunners.
Managing fuel consumption was a critical part of the flight engineer's job during training. Although the crews were still not told of their final destination, they were told they would be flying in excess of 1900 miles during the mission. This required modifications to the B-25 already in progress as well as utilizing techniques to decrease fuel consumption. Detailed logs were kept to calculate the fuel consumption of each aircraft. Significant differences in fuel consumption were noted. One cause of the discrepancy was old and pitted propellers. New propellers, in some cases, could increase the airspeed by as much as 55 mph. A carburetor expert from Bendix arrived at Eglin to adjust the carburetors to maximum efficiency. A new cruise-control chart was created to maximize range by adjusting manifold pressure and propeller settings as weight reduced. Their detailed records indicated the B-25s would burn 78 gallons of fuel per hour fully loaded and decrease to 65 gallons per hour as weight decreased.
First Lieutenant Thomas White, a flight surgeon, had volunteered for the raid. He was informed by Major Jack Hilger that there was no room for a doctor on this mission. Major Hilger would allow him to earn is way onto a crew by training as a gunner. He scored second highest of all the gunners on the firing range and did indeed earn his way onto the mission. His first task was to review the medical kits in the aircraft. The blood type of each airman was recorded on their dog tags. Needed medication, including morphine and antibiotics would prove challenging. Getting the needed vaccines for the crews required intervention from Lt. Col. Doolittle, but was complete by the end of training. More supplies would be acquired upon arrival at the Sacramento Air Depot.
Eglin Modifications
While at Eglin, the mechanics were busy making further modifications to the B-25s. The 265 gallon bomb bay tank leaked. A rubber bladder was inserted that decreased the capacity to 225 gallons. This bladder did improve the problem, but was prone to wrinkle and leak as well. Deicer boots were fitted to the aircraft. Although they would not be needed in Tokyo, they might be needed depending on the landing location. The difficult to master lower turret would be removed. Replacing the Norden bombsight would be one of the simpler fixes. Mechanics also spent some time disassembling and rebuilding the .50 cal. machine guns as well as adding blast plates near the turrets. Arguably, the most important modification for the mission was the carburetor modifications. An expert from Bendix was brought in to adjust the carburetors to maximize fuel efficiency. Several other needs were noted such as new propellers and navigator windows. These parts would be ordered and shipped to McClellan Field where final preparations would be made.
Accidents
The challenge of learning short field takeoffs in such a short period of time did have consequences. The first of those incidents happened during a navigation flight. In the afternoon of March 10, 1942, B-25B SN 40-2254 suffered a nose wheel failure after landing at Ellington Field, Texas. None of the 6 men on board were injured. Pilot Richard O. Joyce had just landed and the aircraft developed a severe shimmy in the nose wheel about 400 feet from the end of the runway. Power was cut to the engines and the nose wheel collapsed. It was determined the cause was a malfunction of the shimmy dampener on the nose landing gear. The aircraft would eventually be repaired, but it would not return to Eglin during training.
The second accident happened on the final day of training. The pilot was First Lieutenant James P. Bates. Lieutenant Miller felt Lt. Bates needed more practice on short field takeoffs. A crew was assembled to include Lt. Miller and loaded into B-25B SN 40-2291. While attempting to take off on the morning of March 23, 1942, the airplane stalled at about 15 to 20 feet in the air. The B-25 crashed severely damaging the airframe. All of the occupants were uninjured. The plane was damaged beyond economical repair and was scrapped. First Lt. Bates, Second Lt. Roloson, and Sgt. Roasch would not participate in the raid. The loss of the second plane caused Captain York to phone the headquarters of the 17th in Columbia. He asked his close friend Lt. Emmens to fly another B-25 to Eglin as a replacement. It should be noted that this B-25 would not be modified for the raid. Due to the nature of this request, no orders for this transfer were issued. As a result, the SN of this B-25 is lost to history.
Deployment
Late in March Lt. Col. Doolittle flew back to Washington to convince General Hap Arnold to allow him to go on the mission. After pleading his case, Lt. Col. Doolittle was given permission only if he also received permission from Brig. Gen. Millard Harmon Jr., his chief of staff. Lieutenant Doolittle raced to Brig. Gen. Harmon's office to ask before General Arnold could speak to him. Permission was granted before Brig. Gen. Harmon really understood what he was asking. Lieutenant Col. Doolittle disappeared as fast as he could. Back at Eglin, First Lieutenant Stintzi had become ill. Diagnosed with an ulcer, there would not be time to wait for him to recover. Now with official permission to go on the raid, Lt. Col. Doolittle announce he would be taking Stintzi's crew.
The time had come. Preparations for the raid were nearing completion and the target date of April 20, 1942 was fast approaching. General Arnold sent a coded message to Eglin. "Tell Jimmy to get on his horse". Ready or not, it was time for the men to end their training and head for California. At 3 a.m. on March 24, 1942, Doolittle informed the men they would be flying cross country to McClellan Field in Sacramento for final modifications. This would be their last training flight. The remaining 22 crews would fly across country at tree-top height. Still unaware of their true mission, they would fly from Florida to California at 100 feet. Many stories were later recorded by the raiders of this flight. Most noted cattle stampedes and farmers running scared. The aircrews decided to have some fun and it would be a memorable flight for many.
Arriving that afternoon was Lieutenant Emmens. He would find most of the crews already gone. Lieutenant Emmens located Captain York and asked for information on the location of the crews. Captain York informed him that the crews had left for the west coast. He further inquired if Lt. Emmens wanted to go on the mission. Because of the loss of the two planes, Captain York felt the mission would be a crew short. Lieutenant Emmens wasted no time in accepting the opportunity and the two headed to their B-25 bound for California.
McClellan Field
On March 25, 1942, the group arrived at McClellan Field. Some supplies ordered by Lt. Col. Doolittle had arrived and others were still on the way. At McClellan, the 60 gallon rubber bag that replaced the lower gun turret would be placed as well as new covers to replace the larger additional bomb bay tank. The liaison radios and tracing antennas were removed from the planes. This mission would be run with radio silence. There would be no need for the extra weight. Parachutes were ordered and fitted. Still cameras were placed in 6 of the B-25s to assess bomb damage. The remaining 16 would get movie cameras. New propellers would be painted and placed on every aircraft. Doolittle also instructed that any burned-out instrumentation lights be replaced. He requested spares placed in the aircraft as much as possible. They would be on their own soon. Any needed parts would have to be available.
In the most serious manor possible, Lt. Col. Doolittle demanded that "Under no circumstances is any equipment to be removed or tampered with on these airplanes. This will be strictly complied with at all times on the Project. Inspectors or Men working on the airplanes finding defective or damaged parts must notify the Project Officer or Project Supervisor of this condition before accomplishing any work." He also specifically stated that no carburetor settings be adjusted. While discussing the mission with some of the crew, Doolittle heard one of the B-25s backfire. He looked out to see one of their planes spitting out black smoke. He rushed over and inquired what the mechanic was doing with that ship. The mechanic responded "We're adjusting the carburetors. They're all out of adjustment.". Needless to say, Lt. Col. Doolittle was more than a little upset.
Carburetor adjustments were not the only issue the raiders had at McClellan. Doc White argued for the needed supplies for his medical kits. In his report, he noted that in many cases the desired supplies were available on the shelves, but the medical supply officer refused to give them up for the mission. The group also had problems getting the needed ammunition as well. All of these issues required frequent phone calls to General Arnold.
There would be no time to fix the changes made to the carburetors. The modifications were nearly complete. Some parts, such as the replacement navigator windows had not arrived. These would catch up to the raiders while they were on the Hornet just outside of San Francisco Bay. The men were as trained as they were going to get. On the afternoon of April 1, 1942, the men flew to the Alameda Naval Air Station in preparation for departure.