The actor, who plays Eric Pollard on the ITV1 soap, recently embarked on a 200-mile journey from Scotland's Fort William to Cape Wrath in aid of Leukaemia and Lymphoma Research.
However, events took an unexpected turn on Sunday when Chittell's fellow challenger Pete Quinn tried to jump a stream and slipped, causing a suspected Achilles tendon injury. As heavy rainfall had led to treacherous conditions, the whole walking team were rescued by helicopter yesterday.
Chittell told the Daily Record: "They came to get us by air, which is actually quite embarrassing because it is not a life-threatening situation, although if they had not got the guys out it would have been a very uncomfortable and very, very slow journey to head back to civilisation. It could have developed into something else.
"It's a little ironic given I have done a bit of charity stuff with search and rescue. Under the circumstances, it wouldn't have been safe to carry on. We were using daylight as much as possible and head torches but because the rainfall was so great, there were holes where you didn't see them.
"That's another reason why I thought it best not to continue, even if we dropped Pete off. It's hugely disappointing."
The 63-year-old, who trained extensively in preparation for the trek,, added that he intends to return and complete the challenge at a later date.
"We'll be back, without a doubt," he said. "It's got to be done."
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