• – as search zeroes in on two oil patches found floating on sea
  • Search and rescue chief says plane is most likely ‘at the bottom of the sea’
  • ‘Suspicious objects’ spotted 1,120km from where Airbus A320 lost contact
  • Indonesian helicopter saw two oily spots in search area Monday afternoon
  • Experts claim jet may have stalled because it was flying 160km too slow
  • Last contact was request by pilot to increase altitude due to bad weather
  • Air traffic control couldn’t grant request because another plane was in way
  • The AirAsia flight QZ8501 departed Indonesia early on Sunday morning 
  • It was scheduled to land at Singapore’s Changi Airport on Sunday morning
  • Pilot contacted air traffic control at 6.12am – lost contact five minutes later 
  • There were a total of 155 passengers on board and seven crew members 

A pilot on board the missing AirAsia plane was denied a request to increase altitude to avoid rough weather shortly before the jet disappeared, it emerged today.

In the last communication with air traffic control, one of the pilots asked permission to turn left and climb from 32,000ft to 38,000ft due to storm clouds.

However, the request could not immediately be granted because another plane was in the airspace at 34,000ft, said Bambang Tjahjono, director of the state-owned company in charge of air-traffic control.

By the time clearance could be given, Flight 8501 had disappeared, Tjahjono said.

It came as planes hunting for the Airbus A320 revealed they had spotted objects and oil patches in the sea in the search zone.

Jakarta’s Air Force base commander Rear Marshal Dwi Putranto said an Australian Orion aircraft had detected suspicious objects around 1,120km from the point of last contact.

An Indonesian helicopter also spotted two oily spots this afternoon close to where a group of Indonesian fishermen claimed to have heard a crash near the island of Pulau Nangka.

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Holding out hope: Members of Indonesia's Marine Police hold a briefing on a search and rescue vessel prior to heading to sea to search for the missing AirAsia flight QZ8501 at Pangkal Pinang port in Sumatra Island

Holding out hope: Members of Indonesia’s Marine Police hold a briefing on a search and rescue vessel prior to heading to sea to search for the missing AirAsia flight QZ8501 at Pangkal Pinang port in Sumatra Island

Operation: The search ships joined the hunt as officials said objects had been spotted in the sea

Operation: The search ships joined the hunt as officials said objects had been spotted in the sea

Members of Indonesia's Marine Police pray on board a search and rescue ship before embarking on the hunt for the missing AirAsia flight QZ8501 at Pangkal Pinang port in Sumatra Island

Members of Indonesia’s Marine Police pray on board a search and rescue ship before embarking on the hunt for the missing AirAsia flight QZ8501 at Pangkal Pinang port in Sumatra Island

Inconsolable: Family members of passengers on board missing AirAsia flight QZ8501 cry at a waiting area in Juanda International Airport as they wait for news of the search and rescue operation

Inconsolable: Family members of passengers on board missing AirAsia flight QZ8501 cry at a waiting area in Juanda International Airport as they wait for news of the search and rescue operation

Mystery: The flight went missing at 6.17am local time on Sunday while travelling from Indonesia to Singapore with 162 people on board. An Indonesian helicopter saw two oily spots in the search area Monday afternoon

Mystery: The flight went missing at 6.17am local time on Sunday while travelling from Indonesia to Singapore with 162 people on board. An Indonesian helicopter saw two oily spots in the search area Monday afternoon

Rear Marshal Dwi Putranto said the objects were spotted near Nangka island, about 160 kilometres south-west of Pangkalan Bun, near central Kalimantan.

The announcements will bring further anguish to relatives of the 162 passengers and crew who are desperately clinging to hope they may find survivors despite one official saying the jet was most likely ‘at the bottom of the sea’.

But he added: ‘We cannot be sure whether it is part of the missing AirAsia plane. We are now moving in that direction, which is in cloudy conditions.’

Indonesia’s vice-president, Jusuf Kalla, also said there is ‘insufficient evidence’ the objects were from the missing AirAsia plane.

Waters in the search area, which is roughly the size of California, are not particularly deep at between 130ft and 160ft.

The flight went missing at 6.17am local time on Sunday while travelling from Indonesia to Singapore as speculation on the cause of the disappearance centred on weather, speed and an older radar system.

AirAsia confirmed there were 155 passengers on board – including 138 adults, 16 children and one infant – and also stated there were two pilots, four flight attendants and one engineer on board.

Nationalities of passengers and crew on board are one Singaporean, one Malaysian, one British, one French, three South Koreans and 155 Indonesians.

Earlier Monday, Indonesia search and rescue chief Henry Bambang Soelistyo said it seemed certain that the plane had crashed.

‘Based on the co-ordinates that we know, the evaluation would be that any estimated crash position is in the sea, and that the hypothesis is the plane is at the bottom of the sea,’ he said.

Distraught family members of passengers from the missing AirAsia flight try desperately to comfort each other at the crisis centre of Juanda International Airport in Surabaya, Indonesia

Distraught family members of passengers from the missing AirAsia flight try desperately to comfort each other at the crisis centre of Juanda International Airport in Surabaya, Indonesia

Grief: Relatives and next-of-kin sob while waiting for the latest news on the search for the missing Air Asia jet

Grief: Relatives and next-of-kin sob while waiting for the latest news on the search for the missing Air Asia jet

Family members of people on Air Asia flight QZ8501 pray together at Juanda International Airport

Family members of people on Air Asia flight QZ8501 pray together at Juanda International Airport

AirAsia has set up emergency briefing rooms for family members of the missing passengers at both airports in Indonesia and Singapore

AirAsia has set up emergency briefing rooms for family members of the missing passengers at both airports in Indonesia and Singapore

The last communication from the cockpit to air traffic control was a request by one of the pilots to increase altitude from 32,000 feet to 38,000 feet because of the rough weather.

Air traffic control was not able to immediately grant the request because another plane was in airspace at 34,000 feet, said Bambang Tjahjono, director of the state-owned company in charge of air-traffic control.

By the time clearance could be given, Flight 8501 had disappeared, Tjahjono said.

The twin-engine, single-aisle plane, which never sent a distress signal, was last seen on radar four minutes after the last communication from the cockpit.

Search efforts for the plane’s wreckage resumed on Monday and have been focused around the area of the Java Sea near Belitung.

Distress: Relatives comfort each other as they wait for the latest news on the search of the missing jetliner at Juanda International Airport in Surabaya, East Java, Indonesia

Distress: Relatives comfort each other as they wait for the latest news on the search of the missing jetliner at Juanda International Airport in Surabaya, East Java, Indonesia

Relatives of missing Air Asia QZ8501 passengers cry at Juanda International Airport in Indonesia as they wait for any news about their loved ones

Relatives of missing Air Asia QZ8501 passengers cry at Juanda International Airport in Indonesia as they wait for any news about their loved ones

There are scenes of anguish at the Indonesian airport as family and friends wait anxiously

There are scenes of anguish at the Indonesian airport as family and friends wait anxiously

Relatives hold a picture of the Herumanto Tanus family as they wait for news from the missing AirAsia plane at Juanda Airport, in Surabaya, Indonesia

Relatives hold a picture of the Herumanto Tanus family as they wait for news from the missing AirAsia plane at Juanda Airport, in Surabaya, Indonesia

Boats have been sent from Tanjung Pandan, the largest town on Belitung Island, but are not expected to reach the area until midnight local time, due to inclement weather and sea conditions, reported The Sun Herald.

It comes after aviation experts said the flight was flying ‘about 160 km/h too slow’ when it encountered bad weather conditions.

Aviation expert Geoffrey Thomas spoke to several check captains and believes the pilot of QZ8501 encountered difficult weather conditions but flew too slow in his efforts to avoid it.

‘The QZ8501 was flying too slow, about 100 knots which is about 160 km/h too slow. At that altitude that’s exceedingly dangerous,’ Mr Thomas said.

‘Pilots believe that the crew, in trying to avoid the thunderstorm by climbing, somehow have found themselves flying too slow and thus induced an aerodynamic stall similar to the circumstances of the loss of Air France AF447 to crash in 2009.’

A member of Indonesian National Search and Rescue Agency shows a map of the search area on screen during a briefing prior to a search and rescue operation of the missing AirAsia flight QZ8501

A member of Indonesian National Search and Rescue Agency shows a map of the search area on screen during a briefing prior to a search and rescue operation of the missing AirAsia flight QZ8501

A member of the Indonesian National Search and Rescue Agency points to a map of a search area

A member of the Indonesian National Search and Rescue Agency points to a map of a search area

Search efforts for the plane's wreckage resumed on Monday and have been focused around the area of the Java Sea near Belitung

Search efforts for the plane’s wreckage resumed on Monday and have been focused around the area of the Java Sea near Belitung

The Air France AF447 crashed into the Atlantic Ocean in 2009 while en route from Rio De Janeiro to Paris.

‘I have a radar plot which shows him at 36,000 feet and climbing at a speed of 353 knots, which is approximately 100 knots too slow … if the radar return is correct, he appears to be going too slow for the altitude he is flying at,’ Mr Thomas said.

Mr Thomas said this should not happen in an A320, so it appears as though it was related to extreme weather conditions.

‘He got caught in a massive updraft or something like that. Something’s gone terribly wrong,’ he said.

‘Essentially the plane is flying too slow to the altitude and the thin air, and the wings won’t support it at that speed and you get a stall, an aerodynamic stall.’

The A320, while sophisticated, is not equipped with the latest radar, Mr Thomas said.

Aviation expert Geoffrey Thomas believes the plane was flying too slowly 

Captain Iriyanto, pilot of the airline's missing flight QZ8501, in a picture posted on social media by his daughter Angela Ranastianis. His nephew has said Capt Irianto as 'a very caring person'

Aviation expert Geoffrey Thomas (left) believes the plane, piloted by Captain Iriyanto, was flying too slowly

AirAsia CEO Tony Fernandes visited Juanda International Airport in Indonesia while the search was underway on Sunday

AirAsia CEO Tony Fernandes visited Juanda International Airport in Indonesia while the search was underway on Sunday

AirAsia chief: ‘Passengers’ families are our number one priority’

The radar used by the A320 can sometimes have problems in thunderstorms and the pilot may have been deceived by the severity of these particular ones.

The latest technology radars, which were pioneered by Qantas in 2002, can give a more complete and accurate reading of a thunderstorm, but they will not be certified for the A320 until next year.

‘If you don’t have what’s called a multi-skilled radar you have to tilt the radar yourself manually, you have to look down to the base of the thunderstorm to see what the intensity of the moisture and the rain is, then you make a judgment of how bad it is. It’s manual, so it’s possible to make a mistake, it has happened,’ Mr Thomas explained.

Meanwhile, the billionaire CEO of AirAsia described missing flight QZ8501 as his ‘worst nightmare’ as the massive air and sea search for the plane resumed at first light on Monday.

Tony Fernandes spoke of his horror over the situation after the plane lost contact with air traffic control with 155 passengers and seven crew members on board at about 6.17am local time, a short time after the pilot asked to deviate from the flight path due to ‘bad weather’.