Andrew Probert (designed the Romulan Warbird):
"I love even numbers, so the warbird is 4,440 feet long (= 1353m). The thing is, I provided this image to the producers purposely to suggest that the scene be filmed with the Enterprise in front, obviously closer to us, yet the warbird is still larger. Unfortunately the visual effects people reversed the shot and you really had no idea how much larger the Romulan ship was." (Star Trek: The Next Generation 365, p. 132)
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| design sketch by Andrew Probert |
Here you can have a look on my Star Trek Size Comparison Charts including the Romulan Warbird.
I think the impression from TNG "The Neutral Zone" is the only screencap in which you can realize the size.
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| screenshot by trekcore.com (TNG "The Neutral Zone") |
A second good impression is seen during the Breen counter-attack on Chin'toka from Deep Space Nine "The Changing Face of Evil".
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| screenshot by trekcore.com (DS9 "The Changing Face of Evil") |
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| screenshot by trekcore.com (DS9 "The Changing Face of Evil") |
