Shortly before he briefed his cabinet on Thursday evening, Rishi Sunak put down the phone to Egypt’s President Abdel Fattah El Sisi with some satisfaction.
He had just been given clearance for RAF jets to fly over Egyptian airspace on their way to strike Houthi targets in Yemen more than 2,500km from their base in Cyprus.
President Sisi’s decision was a “show-stopper” according to one defence source, as without it the RAF would have had to thread their way over Israel down the Gulf of Aqaba, with all the political difficulties that would entail.
Egypt was on board with the clearances, Mr Sunak was delighted and at 7.30pm GMT (10.30pm Yemen), he ordered four Typhoon fighter-bombers to take off, accompanied by a Voyager air supply tanker, in his first military action as prime minister.
Egypt collects more than $9.4 billion in income from transiting vessels and the Suez Canal has witnessed a significant shortfall in shipping traffic.
Strike package
The Typhoon force were not the only warplanes taking to the sky for what would be a considerable “strike package” against the Houthis.
At about the same time a US Rivet Joint surveillance plane took off from Doha, Qatar, ready to eavesdrop on Houthi and Iranian communications before and after the attack.
Curiously, Iranian spy ship MV Behshad, that has probably assisted the Red Sea shipping attacks with targeting information, partially withdrew from the area, potentially tipped off by western powers keen to avoid further escalation.
On board the US Dwight D Eisenhower in the southern Red Sea, up to two squadrons of highly capable FA-Super 18 Hornets readied to take to the skies.
Ahead of them a Growler electronic warfare aircraft, designed to jam enemy air defence radar, would have been already circling the skies close to the targets ready to hit Houthi radars with their Harm anti-radiation missiles.
A US Navy P-8 Poseidon intelligence plane and Hawkeye air controller also joined it.
Below the surface, sailors on board an Ohio-class guided missile submarine readied their Tomahawk cruise missiles for departure via its numerous launch tubes.
Allied command
At the Combined Air Operations Centre (CAOC) in Doha, officers from Britain and America were joined by colleagues from Australia, the Netherlands and Canada to assist in the planning, logistics and intelligence gathering.
The operations centre was used as the main location for co-ordinating the multi-strike raid.
The four RAF Typhoons were instructed to rendezvous with the Voyager, with two aircraft at a time refuelling somewhere over the Red Sea.
Under their wings were six Paveway IV precision-guided bombs ready to be armed for dropping after the 2,500km flight from Cyprus.
Above the Eisenhower, the Super Hornets formed strike teams awaiting the final signal that the operation was on.
Tomahawk plume
The surface of the Red Sea erupted in plumes of water as a wave of Tomahawks breached the surface shortly after 2am Yemen time.
Travelling at 900kph just three metres above the waves, the weapons separated to head to their targets at seven different sites spread across the Houthi-held area of western Yemen.
At precisely 2.30am the first 450kg warhead detonated on a military target that was likely either a radar station or surface-to-air missile site. At 2.31am the dashcam of a taxi driver in Hodeidah airport captured the explosion in the immediate aftermath of the hit.
The Houthis now knew they were under extensive attack but just how substantial, they were about to find out.
Paveway assault
The Typhoons dropped down to below 10,000 feet as they split into two pairs to head towards their targets of Bani, where drones and reconnaissance equipment were stored, and Abbs airfield.
Carrying the Paveways, instead of the stand-off Storm Shadow cruise missiles that could be released from a distance of 200km, they had to be directly over the target.
Using the high-resolution imagery on their Litening targeting pod they flew overhead.
“They wanted to have visual identification of the target before dropping them,” said military analyst Tim Ripley. “That means that they were not sure what were they were going to hit before they arrived overhead as there is a mobile aspect to Houthi forces.”
At 2.45am on Friday, up to 12 Paveways hurtled down to the military installation in Bani, in north-western Yemen, striking the Houthi’s arsenal of reconnaissance and attack drones.
A number of buildings involved in drone operations were also among the targets.
Intelligence gathered over the last few weeks had shown that Abbs had been used to launch cruise missiles and drones over the Red Sea. The site echoed to the blast of Paveway bombs as it too was hit.
Super Hornet strike
The estimated 15 Super Hornets that had taken off from the Eisenhower separated into strike pairings as they headed for a number of other locations, focusing around the capital, Sanaa.
Using either their 900kg Paveway III-guided bombs or Jdams (Joint Direct Attack Munition) they hit radars, missile and drone launch sites, weapons storage areas, air defences and munition depots.
In total, the coalition struck 60 targets in 16 locations in Yemen using more than 100 precision-guided munitions. These included the military installations at Sadeh, Zubaydah and Tiaz, as well as the naval base at Hodeidah.
The Houthis stated that there had been 73 strikes in Sanaa and that five people had been killed.
Expert assessment
While it is still too early to find out exactly what damage the strike caused – what the military calls “battle damage assessment” – the operation could have substantially dented the Houthis hardware.
“They have struck targets that will degrade the Houthis’ maritime strike capability,” said military expert Sam Cranny-Evans.
“Also, it's difficult to interpret the things that have been hit as an escalation, rather it's a proportionate response to what has already happened.
“This also shows that the US and UK are willing to use quite a lot of force and that's an important thing because deterrence is a lot about messaging and credibility. They are saying ‘this is what we did in one night, don't make us open this up again’.”
But Brig Ben Barry, of the IISS think tank, argued that it would be difficult to assess the damage as much of the Houthi kit could be hidden away.
He added that the rebels could respond against shipping by using artillery or firing surface-to-surface rockets that have yet to be used at scale.
There was also a potential political fallout.
“The Arab street is going to see this as a smoking gun, showing that the UK and the US have definitely gone over to the Israeli side,” said Brig Barry.
“It may make a difference in the Red Sea, where the Houthis choose to reduce or abandon their attacks, but it actually increases the wider risk of escalation.”
There is also a suggestion that the Houthis could make the American airbase in Djibouti, which is about 25km from Yemen, a target.
