On January 31, 2024 workers from Big D Builders were
erecting the steel frame for a new hangar at the Jackson Jet Center, which is
located beside the Boise Airport at 4049 West Wright Street. The hangar was to
be 45 feet tall and cover an area of 39,000 square feet. It was about 310 feet
wide by 126 feet deep. But around 5:00 PM it collapsed with the trusses changing
to the shape of a capital letter M (as shown above in my image), killing three
people and injuring another nine.
Some details are discussed in an article by Sally Krutzig in
the Idaho Statesman on February 20, 2024 titled Rescue operations at Boise
building collapse included 3 people stuck in aerial lifts:
“In his review, Boise Fire Department Training and Safety
Capt. Steve Madigan wrote that ‘it appeared that the structure somehow failed
at the ridge line and caused all the columns to pull inward.’ Initial reports
indicated 16 people were at the scene when the building went down, and police
and fire crews helped wounded victims who were able to walk leave the area,
according to Madigan. The building’s columns ‘were leaning at 45 degrees
(approx.) and the bolts securing them to the ground had either sheared off or
tore the bottom flange of the steel as they fell,’ Madigan wrote.”
Another article by Alex Brizee at the Idaho Statesman on March
6, 2024 is titled ‘Did not look right’: Workers flagged concerns before deadly
Boise hangar collapse. It includes an overhead drone shot of the collapsed
hangar, which has fallen to one side. That suggests a directional load, perhaps
due to wind gusts. The article began by stating:
“Several employees who worked at the site of a deadly
building collapse on Boise Airport grounds told police they had noticed bending
beams, snapped cables and overall structural issues, according to Boise Police
Department investigative reports obtained by the Idaho Statesman. Some of these
workers informed the site’s supervisor of the concerns the day before the
hangar crumbled on Jan. 31, killing three people and injuring nine others.
Interviews with employees of Boise-based Inland Crane, which provided equipment
and operators for the construction of the Jackson Jet Center hangar, were
documented in Boise Police Department reports that were released to the
Statesman through a public records request.”
Still another article by Angela Palermo at the Idaho
Statesman on February 2, 2024 titled Was it wind? How a bridge’s failure may shed light on fatal
Boise Airport hangar collapse includes two images of the framing before the
collapse.
OSHA is investigating the collapse and will issue a report within
six months. How an investigation proceeds is discussed in yet another article
by Kevin Goudarzi at Structure on
March 2023 titled The forensic engineering process for
structural failures. On April 17, 2023 I blogged about A great video course on
Epic Engineering Failures and the Lessons They Teach. In that post I discussed the Hyatt Regency walkway collapse,
where a design detail change doubled the applied load – eliminating the intended
factor of safety.