- UK can start bombing ISIS within hours, as it has six fighter jets on standby in Cyprus
- British forces have Brimstone precision missiles, high-tech weapons others don't have
- The U.S. is leading the airstrikes against ISIS in Iraq and Syria
Britain joined the U.S. and its allies in the fight against ISIS -- but any mission will come with a huge price tag.
The UK parliament has approved airstrikes in Iraq against the terror group which prime minister David Cameron has called one of "staggering" brutality.
Cameron had said Britain should join international allies in combating ISIS, an action that he warned would "take not just months, but years."
While the total cost will depend on the intensity and length of operation, past experience can give some guidance, Malcolm Chalmers, research director from the Royal United Services Institute said.
Chalmers pointed to the UK's seven month involvement in Libya through 2011, which cost around $390 million, including missiles and flight hours.
The bill is additional to standard defense budgets, which include staffing costs and weapons spend. Last year, the UK defense budget was $60 billion.
Chalmers said he would expect the cost of ISIS airstrikes to be in the "ballpark," of the Libya operation, "assuming we only use air power and the campaign lasts for a couple of years."
Cameron has said that the mission against ISIS could last "years." However, it is U.S.-led rather than the operation in Libya, in which European countries took the lead.
Cameron, in Friday's debate aimed at convincing parliament to approve airstrikes, said Britain has "unique assets" no other coalition ally can contribute.
Cameron named the Brimstone precision missile, which he said minimized risk of civilian casualties, as one only Britain could contribute. The missiles can target convoys as well as fast moving, fleeting targets that were previously harder to strike, according to IHS Jane's senior weapons analyst Ben Goodlad.
The Brimstone, which travels at supersonic speed, is a 1.8-meter missile weighing just under 50 kg. Advanced radar equipment enables it to guides itself to the target, so pilots don't need to maneuver to release it. IHS Jane's estimates each missile costs around $240,000.
Brimstone missiles are compatible with the UK's Tornado GR4 aircraft. The aircraft were used by British troops for relief missions in northern Iraq just over a month ago. Six of these are ready for deployment at the UK's RAF base in Cyprus.
Flying the Tornadoes costs around $57,000 per hour, according to information released in a parliamentary debate about Libya in 2011. From the Cyprus base, the aircraft could reach Iraq in just over an hour.
Goodlad said the RAF also has Tornado's Storm Shadow cruise missiles, which cost $1.3 million each, and submarine-launched Tomahawk cruise missiles. These can be used to target areas that can't be accessed by planes, for example due to defenses, and cost round $1.5 million each.
U.S. forces have been using Tomahawk missiles for airstrikes in Syria earlier this week -- dropping 47 of them on Monday evening.
In total, the U.S. has conducted 20 strikes in Syria and 198 in Iraq from August 8 through September 23.
Many of those operations weren't included in the Pentagon's daily average spending figure of $7.5 million at the end of last month.