The USS George Washington will expand search-and-rescue operations and provide a platform for helicopters to move supplies, the White House said.
The top US commander in the Philippines told the BBC that US military support would be on an unprecedented scale.
Some 11 million people have been affected by the typhoon.
Although the official death toll stands at more than 2,300, local officials and aid workers fear it could rise much higher.
With images of the suffering flashed around the world, a huge international aid effort has swung into operation.
The USS George Washington arrived on Thursday along with its escort ships, the US Navy said. Two US destroyers have already arrived in the Philippines and other US vessels are expected to arrive in about a week, it added.
On Wednesday the US also ordered the activation of a hospital ship, the USNS Mercy. However, if deployed it would not reach the Philippines until December.
Marine Brigadier General Paul Kennedy, commanding general of the 3rd Marine Expeditionary Brigade in Japan, told the BBC that the US aid effort was being stepped up to a level that has "probably never been applied" to a humanitarian crisis.
He said the arrival of the USS George Washington would triple the number of available helicopters. As well as search and rescue capabilities, the helicopters can deliver hundreds of thousands of gallons of water every day, he added.
Other countries have also pledged help in the shape of financial aid, relief supplies or emergency teams.
Britain is sending a team of medical experts, a Royal Navy warship and an RAF transport aircraft.
Japan is also preparing to send up to 1,000 troops as well as naval vessels and aircraft, Defence Minister Itsunori Onodera said.
Orla Fagan, at the UN's Humanitarian Affairs office in Manila, said that after a slow start, the aid effort was now accelerating.
"People are angry, they are distressed, they are traumatised, and we are trying to get this stuff out to them," she said.
It roared into the eastern and central islands of the Philippines on Friday, flattening buildings, uprooting trees and sending a huge storm surge into coastal areas.
Philippine Cabinet Secretary Rene Almendras said his country was facing "the largest logistics operation that we've ever done in the history of the Philippines".
Some residents have expressed anger at the slow speed of the government relief effort but Mr Almendras said authorities had been overwhelmed.
"The volume of food packs, the volume of rice, the volume of canned goods is being handled, repacked and transported now - that's never been done on this magnitude," he said.
"But we accept the fact that our operations are supposed to reach out to everyone - and we will."
Growing panic
UN humanitarian chief Valerie Amos, visiting the devastated city of Tacloban, said the situation was desperate with residents left without food or fresh water for five days.
"The priority has got to be, let's get the food in, let's get the water in. We [had] a lot more come in today, but even that won't be enough," she said.
"There are still areas that we have not been able to get to where people are in desperate need... I do feel that we have let people down."
Tacloban's airport was left in ruins by the storm, but in recent days US military planes have been arriving with World Food Programme supplies. A French-Belgian field hospital has also been set up.
The number of US military personnel on the ground is expected to triple from just over 300 now to more than 1,000 in a week, officials said.
Manila has sent troops to Tacloban to keep law and order, but correspondent say there is a growing sense of panic.
On Wednesday there were reports of shots being fired in a street and of a teenager being stabbed in the stomach.
In some areas survivors have resorted to digging up water pipes and extracting fuel from reservoirs at petrol stations.
Police spokesman Reuben Sindac told the BBC that security forces were now in control of key installations, preventing looting and ensuring the safety of aid deliveries.
Cebu governor Hilario Davide told the BBC that he was "concerned" but hoped looting would not take place in Cebu.
"As long as they know that food and water are forthcoming, I'm sure that people will learn to be patient but of course we hear already reports of people getting impatient, especially the islands because it seems there's been a delay in the delivery of these relief goods."
Health experts have warned that the worst-affected areas are entering a peak danger period for the spread of infectious diseases.
