Failure Knowledge Database / 100 Selected Cases

B25 Bomber Crashes into the Empire State Building
July 28,1945, New York, USAby Masayuki Nakao(Tokyo University, Institute of Engineering Innovation)
A B-25 bomber that was about to land in Newark Airport (about 8 miles west ofManhattan Island) crashed into the 79th floor of the Empire State Building due todense fog. This crash caused a large scale fire in the 79th and 80th floors, and took thelives of 14 people. One of the engines flew into an elevator shaft, causing fire on theground floor. Since the bomber did not have much fuel left, the crash did not affect theintegrity of the building.

Fig. 1 B25 Bomber Crashed into the Empire State Building [5]１．EventA B-25 bomber that was about to land in Newark Airport (about 8 miles west of
Manhattan Island) crashed into 79th floor of the Empire State Building due to dense fog.
This crash caused a large scale fire in the 79th and 80th floors and killed 14 people.
One of the engines flew into an elevator shaft and caused fire on the ground floor. The
integrity of the building was not affected.
２．Course
On the morning of July 28, 1945, a US Army B-25 bomber（Wingspan: 67 ft 6 in,Length: 52 ft 11 in）was heading for Newark Airport in New York.

In the dense fog in

New York, the pilot lowered the altitude to land. The B-25 bomber flying at 250 miles
per hour crashed into the North side of 79th floor of the Empire State Building at 9:49
am. The crash caused a fire in 79th and 80th floors.

One of the engines fell throughthe elevator shaft and caused fire at the ground floor.

14 people died in this accident.

1Failure Knowledge Database / 100 Selected Cases

The accident did not affect the integrity of the building and resulted in 1 million dollars
in damage to the building (value of that time).

The building returned to business 2days after the accident.
３．CauseThe B-25 bomber’s pilot was a 27-year-old veteran of 34 bombing missions overGermany, but crashed into the building due to the dense fog.

Although B-25 bomber

could hold 3,700 liters of fuel, fortunately it only had small amount of fuel left since it
was close to the destination, and did not cause significant damage to the building.
４．Immediate Action
Unknown
５．Countermeasure
Since this accident, skyscrapers have been designed to tolerate airplane crashes. 55
years later, when terrorists high-jacked B767 passenger planes and flew into theWorld Trade Center buildings, the buildings avoided immediate collapse.

B767

planes have wing-span of 154 feet and length of 157 feet. They are about 3 times
bigger than B25.

In addition to wide range of damages to the structures such ascolumns by the impact, fires broke out while fireproof covering fell off due to thecollision impact.

High temperature from the fire significantly reduced the strength ofthe metal columns, causing some columns not to hold the weight of upper floors.

Thelower floors started collapsing in chain reaction, and finally the whole building fell as
everyone knows.
６．SummaryOriginal plan for the antenna on the Empire State Building was to be used as amooring mast for Zeppelin.
never carried out.

However, after the Hindenburg explosion, the plan was

They probably never considered an airplane to crash into thebuilding when they were designing the skyscraper, but the damage to the building wassmall.

However, who would have thought the world trade center buildings would be

demolished by terrorists crashing into them with high-jacked passenger planes.
７．Knowledge
Unexpected and unpredictable accidents occur. However, it is important to analyze
occurred accidents and have “damage estimate” of potential accidents in order to beready for immediate actions.
“Damage Estimate” is to estimate in advance what type of disasters may occur in whatarea or region, and what type of damage may result.

By performing damage estimates,

we can forecast how many buildings may be damaged or flooded in which area and2

Failure Knowledge Database / 100 Selected Cases

where the power outage takes place.

From the results of damage estimation, we canmake plans and preparation.
８．On The SideSkyscraper race in New York started in early 20th century and ended when the Empire
State Building was built.

Being 203.4 feet higher than the Chrysler Building built in

1931, the Empire State Building is 1282.8 feet in height and has 102 stories (1470 feetincluding the antenna). Due to a limited amount of space, columns, windows, window
frames were pre-fabricated in the factories.

60,000 tons of steel was brought from thesteel mills in Pennsylvania, 500 km away.

4,000 people worked on the building which

was completed in one year and 45 days.

The cost of the building was estimated to be$50 million, but the cost of the building turned out to be about $24.7 million because
the Great Depression significantly lowered labor costs.
The Empire State Building officially opened on May 1, 1931 with President Hoover
lighting up the tower with a push of a button from Washington DC.
However, due to the depression, only 25% of the building was being occupied at thebeginning and people called it “Empty State Building.

They left lights on the vacant

offices until they were occupied.
People say “Fools and monkeys love to climb high” and fools and engineers are thesame.

They like to “build something big.”

As a result, a huge bridge falls every 30years.

They also like to “build something fast”.

As a result, England’s railway speed

competitions got dangerously overheated in 19th century.

One of the contributing

factors for the Titanic accident in 1912 was also trying to beat the record time forcrossing Atlantic Ocean.

As a result of “Wanting to build something tall”, people

competed in building sky scrapers in 1930’s in the US, in 1990’s in Japan, and in 2000’sin China.
＜References＞[1]

B25 bomber:

http://en.wikipedia.org/wiki/B-25_Mitchell[2]

BBC –h2g2 –Empire State Building：
http://www.bbc.co.uk/dna/h2g2/alabaster/A854237[3]

Official site of the Empire State Building:
http://www.esbnyc.com/tourism/index.cfm?CFID=13224133&CFTOKEN=9989231[4]

Official site of the Empire State Building:
http://www.esbnyc.com/tourism/tourism_history.cfm?CFID=13175735&CFTOKEN=51005502[5]

SHIPPAI HYAKUSEN(100 failure cases) by Masayuki Nakao, publishedby Morikita Shuppan Co.（2005）
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