Scottish soldiers from Catterick barracks in North Yorkshire, from the 100-strong A Company of the 4th Battalion, Royal Regiment of Scotland, have now joined more than 100 firefighters who have been battling the Saddlewoorth Moor blaze since Sunday.
-> Have a go hero rescues two children from Yorkshire riverA major incident has been declared, with around 40 homes evacuated on Tuesday as seven square miles of Saddleworth Moor has gone up in flames, blanketing the Greater Manchester region and beyond in smoke and ash.
Tony Hunter, assistant chief fire officer of Greater Manchester Fire and Rescue Service (GMFRS), said they have used high-tech equipment, helicopters dropping water and backbreaking work using paddles to beat out the flames.
He said there had been a "significant effect" on the blaze in the past 24 hours and work was continuing with the help of the Army.
"We have made significant improvements but I would put an air of caution there though, we had a similar occasion yesterday where we thought we were on top of it and it flared up."
Major Phil Morgan, commanding the Army detachment, said: "We meet every challenge and commit 100% in what we do.
-> Son pleads with judge for leniency after driver killed his mum"Currently we have broken our boys down into various locations and we are beating the fire with paddles and we are supporting them by moving equipment, we are putting water on the fires and we are doing everything we can to stop this fire at the moment.
"We are truly really happy and excited to be here and the boys are cherishing every moment of it."
Mr Hunter cautioned that while the fire was now "contained and under control" he said "things can develop" and if the wind blows the flames back on to the moors it will act as a "fuel source" for the fire.
He said the operation could last for weeks before the fire burns itself out, though the Army deployment is for an initial 48 hours.
Mr Hunter said a good downpour of rain was needed to saturate the dry ground and vegetation - but none is forecast for days as the heatwave continues.
Dave Saxon, director of operations at Tameside Council, said the local authority was monitoring air quality, which had improved on Thursday, and there had as yet been no increase in GP appointments or attendance at A&E.
Fire chiefs say they are "not confident" of finding out how the fire began, given the size of the blaze, but there was no evidence it had been started by BBQs or off-road bikers.
Around 10 fire engines, along with specialist vehicles, helicopters, mountain rescue and Army trucks, are now deployed at Swineshaw Reservoir, Stalybridge, as an operating base.
If the fire worsens, GMFRS will be able to call out an RAF Chinook helicopter, based at RAF Odiham, Hampshire.
It would be used to lift a high-volume pump, capable of pumping 7,000 litres of water a minute, to pump water up on to the moors.
Seven fire engines from Greater Manchester were sent to support their colleagues in Lancashire to tackle another moorland blaze at Winter Hill near Rivington shortly after 3.10pm on Thursday.
Some 60 firefighters are involved in the operation.
Lancashire Fire and Rescue Service tweeted: "12 fire engines are dealing with a moorland fire approx 1km sq in size at Winter Hill. Keep your windows & doors closed if you're close to the smoke."