On the day that Iran hit American bases in Iraq, which would spark an FAA NOTAM for US civil airlines, US airmen and solider to avoid the Persian Gulf (Arabian Gulf), a Boeing 737-800 from Ukraine Airlines crashed in Teheran shortly after take off killing all on board. At this point, the cause of the crash is unknown.
What is known about Flight PS752
At this point, we do know that Flight PS752 was supposed to depart at 05:15 according to Flightradar24 but did not depart until 06:12 from Tehran Imam Khomeini International Airport. The flight was operated by a 3.6 year old Boeing 737-800 from Ukraine International Airlines leased from Varangian Leasing with registration UR-PSR. The aircraft which reportedly had 167 passengers and 9 crew members on board lined up on runway 09R at 02:41 UTC with destination Kiev. The last ADS-B data shows the plane slightly below a calibrated altitude of 8,000 feet and a speed of 275 kts.
Boeing, the manufacturer of the aircraft has said it is gathering more information:
We are aware of the media reports out of Iran and we are gathering more information.
— The Boeing Company (@Boeing) January 8, 2020
As the crash occured in Iran, the Iranian aviation administration should lead the investigation in line with ICAO conventions accompanied by investigators from the type certificate issuing country, the NTSB, and the original equipment manufcturers, Boeing. At the time of writing a full statement has yet to appear from Ukraine International Airlines
Ukraine International Airlines fleet
Ukraine International Airlines has a fleet of 40 aircraft consisting of 26 Boeing 737 Next Generation aircraft, 4 Boeing 767s, 3 Boeing 777s and 7 Embraer ERJ-190. Though the airline has Boeing 737 MAX aircraft on order, the crashed aircraft is an aircraft of the previous generation. With an average age of 12.4 years, Ukraine International Airlines operates a relatively young fleet with no prior accidents reported.