Well, if you take a look at your handy dandy copy of Fighting Ships of the Shattered Imperium (FSSI) you'll see that Battle Riders are carried internally (page 29).
How? The Riders are only 30,000 D and the Tenders are a humongous 500,000 D. They carry only 3 or 6, depending on the model. (You can take a look at the Battle Rider (BR) game for another idea; it looks like the FSSI ships were translated, sort of.)
Now I usually have my Riders in the 75,000 D range myself, and I join 4 of them to a 150,000 D Tender, but I haven't actually designed such things with any Traveller variant, so don't go screaming to me that my numbers are impossible...
Perhaps you're refering to the surface area requirement for grapples? Well, one cure is to use internal hangers, the other is to use USL grapples. If you refuel, you have to either use a fuel shuttle or detach the Riders.
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"This is a spaceship! Why did you throw that grenade here?"
"I was just trying to get the bad guys."
"Uh guys,..."
BOOOMM!