* Missile defence in focus after Houthi Red Sea attacks
* Russians absent from show amid Ukraine war
* China's Z-10 attack helicopter makes foreign debut
SINGAPORE, Feb 23 (Reuters) - The Singapore Airshow included the foreign debuts of new weapons systems, growing interest in systems that could destroy ballistic missiles and swat down drones - but it was missing any Russian presence and major defence deals were scarce.
The trade portion of Asia's biggest aviation gathering ended on Friday, with exhibitors packing up their sprawling displays of military hardware, aerospace services, parts and national pride.
After days of demonstration flights, Asian military acrobatic teams took a break on Friday, when no aerial displays were scheduled in advance of the public air show on Saturday and Sunday.
Unlike previous years, there were no Russian companies presenting their wares at the air show. With international sanctions hobbling business and the invasion of Ukraine sapping supplies, competitors said there were opportunities to step in with some Asian operators of Russian gear.
"In this region you have seen a shift away from Russian equipment already," said Robert Hewson of Sweden's Saab . "Of course there are some natural client countries... who stay where they are" in terms of suppliers.
Several Southeast Asian countries, including Malaysia, Indonesia, Vietnam, Cambodia and Laos, also use Russian-made or Soviet Union-vintage equipment, sometimes alongside Western-made gear. Russia's largest arms exporters did not respond to Reuters requests for comment.
Israel's defence industry made a quiet return after being largely absent from the Dubai air show in November in the wake of the Israel-Hamas war - a subject that the companies were reluctant to discuss.
IAI, Rafael, Elbit and the Israeli defence ministry all declined to comment on anything involving the war in Gaza, including the performance of their weapons.
The war wasn't brought up by delegates at the Singapore event and didn't dampen appetite for Israel's missiles, spy gear and aerial drones, two Israeli industry officials at the show told Reuters, asking not to be named because of the sensitivity of the matter.
MISSILES, HELICOPTERS
The barrage of anti-ship ballistic missiles in the Red Sea, meanwhile, led to an interest in systems that could not just protect against those threats, but also smaller, cheaper missiles and drones, attendees said.
On the sidelines of the air show, a senior executive at a U.S. defence contractor said the activity in the Red Sea by Yemen's Iran-aligned Houthis and in Ukraine had caught the attention of potential customers in Asia.
"What we're seeing is demand increase for integrated air and missile defence here," said the executive, who declined to be named because of the sensitivity of the matter. He said that included sensors to detect targets, the weapons to shoot them down and the command-and-control systems tying it all together.
Jeffrey Lewis, director of the East Asia Nonproliferation Program at the Center for Nonproliferation Studies, said the cost of such systems might make it more economical - based on the experience in the Red Sea - to simply try to destroy the attacking weapons on the ground.
"At the end of the day, we turned to offensive systems to strike the launchers," he said. "That implies that defences are a very expensive niche capability. Why shoot the arrow when you can shoot the archer?"
U.S. Navy destroyers are equipped with the Aegis air defence system, with components from Lockheed Martin, among others, which is designed to shoot down aircraft, cruise missiles and ballistic missiles.
Aegis uses RTX subsidiary Raytheon's SM-2, SM-3 and SM-6 missiles to intercept threats. A Raytheon spokesperson declined to comment on whether the company had seen increased interest in missile defence systems since the Houthi attacks began. A Lockheed Martin spokesperson provided public information about increased production of certain systems.
Among the notable weapon systems on display at the show was the Z-10 attack helicopter, made by China's AVIC, which made its first trip outside Chinese territory in Singapore.
China hopes to export the helicopter. Experts and attendees said the number of potential customers might be small in Asia.
"The performance and capabilities of this platform would certainly make it of interest for export," said Malcolm Davis, a senior analyst at the Australian Strategic Policy Institute. He named Laos, Cambodia and Myanmar as possible buyers.
Although several commercial deals were announced at the air show, and "sustainability" was a buzzword throughout, the defence side of the show ended quietly, with discussion of hopes for future sales but no big announcements.
Still, many attendees came away optimistic, with Boeing saying it had seen "substantive customer engagements" with its defence portfolio. (Reporting by Gerry Doyle; Additional reporting by Joe Brock; Editing by Jamie Freed)
