Under the administration of new President Lai Ching-te, Taiwan revamped training for its armed forces to include more nighttime drills and exercises as the democratic island faces greater pressures from China, which claims it as part of its territory.

On Tuesday night, Captain Hsieh Pei-hsun was forced to eject from his single-seat Mirage 2000 fighter after it apparently lost power, the defence ministry said.

The jet crashed into the sea, while Hsieh was rescued about two hours later and transported to a hospital in central Taichung city.

The air force's chief of staff said it had implemented a Tien An -- or "safe skies" -- inspection of its 60-plane Mirage-2000 fleet, which would mean grounding them.

"A special inspection will be carried out for the whole Mirage fleet," Lieutenant General Wang Te-yang said during a news conference. "We also set up a task force immediately to investigate the incident."

Despite the grounding, he said "there will be no pressure or impact on the air force's combat capabilities in the short term".

Taiwan's Mirage-2000 fighters were purchased in 1992 from France in an arms deal that angered China.

They are still a core component of the island's ageing fleet, which also includes F16 fighter jets from the United States, and locally built Indigenous Defence Fighters.

Taiwan's air force and military are up against increasing pressures from China, which has in recent years ramped up incursions by fighter jets and drones around the island -- actions that military experts dub as grey-zone tactics that serve to exhaust the island's armed forces.

In a 24-hour window ending 6:00 am Wednesday (2200 GMT Tuesday), 21 Chinese military aircraft, nine naval vessels and an official ship were detected around the island, Taiwan's defence ministry said.

A subsequent statement said a further 19 Chinese fighter jets, patrol aircraft and drones were tracked around Taiwan, and the defence ministry was monitoring the situation.

Lai visited Hsieh in hospital and said the pilot's condition was stable.

"The people should also know that in order to protect the country, the armed forces not only stick to their posts but also train day and night," the president told reporters after his visit.

"I ask the people to fully support the military and be the backing of the military. This way the military will have more strength to protect the country. Only by defending the country can we have a stable society," he said.

Beijing, which regards Lai as a "dangerous separatist", launched war games simulating a blockade around Taiwan three days after he was sworn in as president in May.

China has said it would never renounce the use of force to bring Taiwan under its control.