The Championship strugglers – yet to win a game this season – were trailing 19-5 by half-time at the Pirates, Lancaster going over for an unconverted score after 15 minutes.
But, the hosts stepped up after the break to secure a convincing Championship Cup win.
Pirates’ tries came from Alex O’Meara (2), Robin Wedlake, Dan Frost, Marlen Walker, James McRae, Javier Rojas Alvarez and Matt Evans.
Will Cargill kicked four conversions, Alvarez chipping in with three.
There was additional disappointment for Carnegie – other than conceding the first penalty of the game in the opening minute to set the tone of the afternoon – as captain and hooker Ben Sowery was forced out of the action with the visitors from Yorkshire trailing only 14-5 at that stage. Adam Brown came in at hooker but, understandably, it took Yorkshire Carnegie time to readjust in the set-piece, time the travellers simply didn’t have on their side.
To their credit, Yorkshire Carnegie did try and attack with the ball. Unfortunately, too much of this energy was expended in their own half and not the opposition’s danger zone.
In Sunday’s other Pool 3 fixture, Nottingham pulled off something of a surprise result by overrunning visitors London Scottish 41-5.
Scottish still top the Pool 3 standings, however, three points clear of Cornish Pirates after five fixtures.
Nottingham are third, level on points with second-placed Pirates by virtue of their inferior points difference which, obviously, gained something of a boost with the win over Scottish, but that uplift was essentially nullified by their own big-margin triumph over Yorkshire Carnegie.
Carnegie, not surprisingly, sit bottom of the four-team table on zero points – no wins from five matches – which all-but mirrors Yorkshire’s Championship league form of one point from six matches.
Cornish Pirates: Holden, O’Meara, Wedlake, Patterson, Evans, Cargill, Davies, Norton, Frost, Mitchell, Romaine, Cutmore, McRae, Kirikiri, Duncan. Replacements: Channon, Walker, Rodman, Clemson, Ryan, Dawson, Rojas, Parata.
Yorkshire Carnegie: Shaw, Lawson, Metcalf, Robins, Magee, Lancaster, Green, Carlile, Sowery, G. Smith, Brady, Bloodworth, Humfrey, W. Hill, Whitehurst. Replacements: A. Brown, Reid, Davidson, Sugars, Bustin, Turner, Whitmore, Finn.