Meet Me at Infinity by James Tiptree Jr.

wouldn’t they make the natives bring it to them?”
    “Never get it. Sops are difficult. Much simpler this way. Also hairier, Drake style.”
    “If this is true, it’s our clear duty to stop it,” said Quent.
    “A la tri-di?” Sylla laughed shortly.
    “Son,” said Imray, “Space Force is long way away. We here, only. What they got down there, Svenka?”
    “Sector Ten was quite correct,” said Svensk. “Unmistakable. They have succeeded in repairing that A.E.V. The shield was on for a minute just now.”
    Quent whistled.
    “Do you mean they’ve got an Armed Escort Vessel? That shield will be a phased englobement—they can sense and fire right through it.”
    “Drake damn good spacer,” Imray told him. “Always watch. We try sneak in, we get fireball in nose. We stuck, looks like.”
    “]e me demande, ” said Sylla, “How do they propose to conflagrate the city?”
    “A good point.” Svensk stretched. “The farms, of course, were fired with portable flamers. This seems a slow method. Possibly irksome as well. I fancy they may intend to use the ship as a mobile torch.”
    “If they hover that low,” Quent said thoughtfully, “they could only use the top half of their shield. An A.E. shield forms in two hemispheres. Same for the sensor field, too. They can’t fully englobe much below a thousand meters.”
    “Ahe!” exclaimed Sylla. “One could thus attack them under the belly, non? But—we cannot get our ship from here to there undetected. And the sled, it functions only in the air… If only we possessed a space-to-air attack pod!”
    “You do,” said Quent.
    They stared at him.
    “The aft rocket turret. Look at your manual.”
    “Manual,” said Imray blankly.
    “In a few early peebees, the aft rocket cell is demountable and converts to a module capable of limited in-atmosphere function,” Quent recited. “The empennage is sealed flush to the hull. You unbolt a stabilizer fin and swivel it around for the delta. I checked it over—it’s there. Didn’t you ever notice the shielding and lock on that thing?”
    “Fantastic,” said Svensk. “Now you mention—but how is it powered?”
    “You couple on an emergency booster and impellor unit from the ship’s drive after the thing is set up and the pilot is inside. Preferably a spare, if you have one—you’ll recall that my inspections terminated at the engineroom bulkhead,” he said bitterly.
    “You sure manual say all that, son?” Imray demanded. “This thing work?”
    “Certainly it says it,” Quent snapped. “How do I know if it works?”
    Sylla licked his chops.
    “Thus, one could employ the thrust while concealed by this moon, and descend without power, avoiding detection because of the small size, and brake after one is below their horizon. One then approaches silently at ground level, on impellors—and when the enemy elevates himself, boom.” He sprang to the shaft. “Let us view this marvel!”
    In the hold Quent showed them the old demount levers, long since obstructed by mail-pod racks.
    “One wonders how orthagonal a trajectory this thing would endure,” said Svensk.
    “Thermallium.” Quent shrugged. “If the delta didn’t come off.”
    “Somebody going to get killed bad.” Imray peered suspiciously into the turret. “For engine I must talk Morgan. Pfoo!”
    “You talked him into harassing me easily enough,” said Quent.
    “No, that natural,” grunted Imray, hauling over to the speaker.
    “Someday that spook will meet a Drake and find out who his enemies are,” said Pomeroy’s voice from the bridge. “They have a party in the city now. Looting. Gives us some time.”
    “Allons, the suits,” called Sylla from the ladder.
    In an hour’s sweating hullwork they had uncoupled the turret and dogged it to the fin. The old sealant was vitrified but the assembly went in with surprising ease.
    “That stuff will burn off,” said Quent. “What a contraption!”
    “The aerodynamics of a rock,” Svensk