The Cottagers skipper inadvertently turned in a Shaun Bartlett header across the six-yard box to provide Charlton with a 34th-minute lead at The Valley.
Although Luis Boa Morte volleyed in an immediate equaliser, Fulham could not find a second goal their dominance deserved and injury-hit Charlton claimed a London derby point.
Both sides, respective Division One champions in the past two years, had to make changes up front.
Fulham had been expected to give a debut to record £11.5million signing Steve Marlet but a knock acquired on international duty in Chile last week kept the Frenchman out.
That meant goalscorer Boa Morte partnering last season's First Division top scorer Louis Saha with Barry Hayles back from Jamaica's latest World Cup qualifiers less than 48 hours.
Alan Curbishley, already bedevilled by injury, had to use a different striking combination for the third consecutive game.
If the problems at The Valley - Charlton have eight first-teamers currently sidelined - were not enough, an over-enthusiastic training ground challenge by Scott Parker on Friday left Jonatan Johansson nursing an ankle injury.
As a result of the Finn's absence, Bartlett played alongside the ineffective Kevin Lisbie before Jason Euell was switched from midfield as Curbishley sought to curtail the visitors' ascendency.
In fact if it had not been for Saha's unusual profligacy in front of goal,
Fulham might have fashioned their second Premiership victory before half-time.
Saha, already with three top-flight goals following 32 in last season's promotion-winning campaign, continuously got into range only to misfire.
He found an early sight of the target but dragged Boa Morte's 13th-minute lay-off.
The Frenchman was a lot closer from his next effort, though, and may have been awarded a penalty after seizing upon Edwin van der Sar's punt up field.
His lob cleared the on-rushing Dean Kiely, who poleaxed the striker with a feet first challenge, but ran the wrong side of the upright and referee Jeff Winter signalled a goal kick.
Fulham's fluency and ability to keep the ball clearly frustrated Curbishley during the first half and the Charlton boss altered from a 5-3-2 to 4-4-2 formation to attempt to counter the visitors' dominance.
Sylvain Legwinski, a £3.3million buy from Bordeaux, was impressive on his first start for the club and shot over the top after some typically measured Fulham build-up play.
But Charlton took the lead, two minutes after captain Graham Stuart had tested van der Sar for the first time with a volley.
Stuart this time fed Powell, whose cross from the left found Bartlett'sforehead at the far post and the South African nodded down for the unfortunate Andy Melville to inadvertently turn into his own net.
It proved only mere respite, though, as Fulham continued to press and Kiely turned away a Legwinski header before the visitors claimed a 38th-minute equaliser.
Stuart lost possession in midfield; Legwinski showed his pace with a run on goal only to be blocked by an alert Kiely and Boa Morte volleyed in the rebound.
Fulham's swift breaks were proving a handful for Charlton to contain and Saha wasted another chance before Kiely produced a smart double save, parrying a Legwinski effort and foiling the predatory instincts of Boa Morte, who was following up.
Curbishley sent on John Robinson - scorer of the only goal in this fixture two years ago - on the resumption in place of Lisbie and the Welsh winger was denied 10 minutes in when his drive was deflected over the bar by Steve Finnan.
Parker then sent a tame volley into the arms of van der Sar but it was Fulham who continued to look the more likely to alter the scoreline.
Boa Morte fired wide after a neat link-up with Saha and Steed Malbranque sliced too high just seconds after coming on as a 62nd-minute substitute.
Saha made way for Hayles 14 minutes from time as Tigana searched for a winner.
But Sean Davis lost his composure at the end of a flowing counter to sidefoot over their best chance and watched another shot cannon to safety off Luke Young.
And it took a point-blank save from Holland number one van der Sar to deny Powell late on.