Japanese Airfields, Equipment & more #35 - revised

Airfields - "Entai"
More common than the "entaigo", both in Japan mainland and overseas, were revetments, emplacements and bunkers, without a protecting roof, called "entai" ("entaigo"- domed bunker). These had various shapes, the most common had the shape of a staple or the Greek letter Π. Occasionally, but not always, tents, nets or tree branches were placed above them to hide the aircraft from enemy prying eyes.

A Zero found in an "entai" at Aslito Airfield, Saipan.

Another Zero inside an "entai" at Katakoka Base, Shumshu Island, Chishima rettō.

At Rabaul, "entai" were present all around the airfields. In this photo, taken on November 2, 1943, during a US raid against Lakunai Airfield, we can see a staple-shaped "entai" right next to the runway and various thatched huts. Note the 251 Kokutai Nakajima J1N1 "Gekko" (Irving), the Mitsubishi Ki-21 Model 2 Koh "Sally" bomber of the 3rd Chutai, 14 Sentai, that has often been mistaken for a Model 1 and another "Sally" under a camouflage net, we saw in a previous post, belonging to the 81 Sentai.

During another raid against Vukanau Airfield in Rabaul, parafrag bombs can be seen falling from US bombers. Note the differently shaped "entai" shielding Mitsubishi G4M bombers.

Another photo of "entai" in Rabaul, protecting Mitsubishi G4M "Betty" bombers.

These more basic "entai" also in Vukanau airfield, include Kawasaki Ki-61 "Hien" (Tony) fighters. Note the tent covering one of the "entai".

In Musashi Airfield, Paramushir Island, sandbags were used to form an "entai" to shield a Zero fighter. Note the tents and the huge hangars in the background. Hangars are called "kakunoko" in Japanese and have their own story, different from the "entai" and "entaigo".

The IJNAF occasionally used stacked fuel drums filled with earth to form blast walls as can be seen in this most interesting photo taken at an unidentified location. Note the cowling and the drop tank lying on the ground and the palm tree branches offering some camouflage.

In Lakunai airfield (Rabaul East), we can see again the fuel drums forming blast walls.

A short clip featuring Zeros taking off from Lakunai airfield (Rabaul East). We can see again the earth-filled stacked fuel drums forming blast walls. Turn on the sound!

But in Lae Airfield we can see that the fuel drums are part of a more complex "entai" with a revetment protecting the rear of the aircraft.

Here's another "entai" more complicated in different ways. First of all, Japanese sources don't agree as to the exact location. Second, they also don't agree as to what's inside these side walls. Some say it was stacks of bamboo, others say that the sides were made of bamboo and dirt filled the centre. 

A detail you probably didn't notice in the previous post is that all the airfields with "entaigo" were IJNAF. There are very few examples of "entaigo" in Army airfields in Japan. The IJAAF, in general, did not use complex "entai" even in mainland Japan, as the photo taken in Narimasu Airfield, Tokyo, featuring a 47 Sentai Nakajima Ki-84 "Hayate" (Frank) testifies. A simple earthen blast wall was deemed enough to protect the fighter. Note the "riyaka" and the tarps we saw in previous posts.

In Japan and overseas, sandbags were occasionally used to form "entai" at IJAAF bases. In this case, it shields a Kawasaki Ki-48 "Lily".

The "entai" found at Chofu Airfield, home of the famous 244 Sentai, were quite original, i.e. there are no known photos featuring similar "entai" in other airfields. The blast walls form Ts with open rears, some covered by bamboo roofs. These roofs were, of course, supposed to hide the aircraft not to work as hangars or offer any bomb protection.