Around 4,000 members of Unite, including security guards, firefighters and engineers, have been voting on a revised pay deal, with the result expected later today.
Muscat: Following an airport-wide strike called on 5 and 6 August by Heathrow Airport staff over a pay dispute, Oman Air has issued a statement for travellers using Heathrow Airport on those dates. "Airport bosses need to heed this latest strike vote and overwhelming rejection by our members of the revised pay offer which offers little over and above the original offer of 3.75 Euro [$4.56 U.S. Dollar] extra a day for many workers".
There was confusion over exactly which flights had been cancelled with passengers waiting for confirmation from airlines.
The 177 cancelations will affect around 30,000 people, many of whom had to wait to hear until this afternoon to find out whether their flight would fly.
Heathrow said passengers should contact their airlines in the first instance to see how they may be affected.
"While the vast majority of flights will be unaffected, some airlines are making arrangements to operate flights from other United Kingdom airports, others will be delaying flights and, unfortunately, a number will be cancelled".
"We apologise for any disruption to your journey".
On Friday night, the airport and Unite were still in Advisory, Conciliation and Arbitration Service (ACAS) negotiations to avert the strike action.
"We expect security queue times to be slightly longer than normal and advise passengers to check our website for detailed information on how to prepare for their flights and when to arrive at the airport", the spokesman said.
She said passengers should contact their airline for more information.
"Unite will not be making any further comment while talks are ongoing".
It says he received a 103.2 per cent pay increase previous year, with his basic remuneration package rising from £2.097 million in 2017 to £4.2 million in 2018.
The British Airline Pilots Association would have to give two weeks notice before the industrial action. The airline carries up to 145,000 passengers a day.