diff --git a/src/combat.c b/src/combat.c
index a5a3fc1..1eff9f4 100644
--- a/src/combat.c
+++ b/src/combat.c
@@ -350,7 +350,22 @@ void combFire(WEAPON *psWeap, BASE_OBJECT *psAttacker, BASE_OBJECT *psTarget, in
 			}
 			else
 			{
-				flightTime = sqrt((double)dist) / 30;  /* Purely a guess, but surprisingly effective */
+				/* Copied out of proj_SendProjectile.  Simplified slightly. */
+				SDWORD dz = psTarget->pos.z - psAttacker->pos.z;
+				SDWORD iRadSq = distSquared + dz*dz;
+				SDWORD iVelSq = psStats->flightSpeed * psStats->flightSpeed;
+				double fA = ACC_GRAVITY * (double)iRadSq / (2.0 * iVelSq);
+				double fC = 4.0 * fA * (dz + fA);
+				double fS = (double)iRadSq - fC;
+
+				if (fS < 0.0)
+				{
+					flightTime = sqrt((double)dist) / 30;  /* Purely a guess, but surprisingly effective */
+				}
+				else
+				{
+					flightTime = (double)dist / (double)psStats->flightSpeed;
+				}
 			}
 
 			if (psTarget->lastHitWeapon == WSC_EMP)
diff --git a/src/projectile.c b/src/projectile.c
index edd4296..2c23122 100644
--- a/src/projectile.c
+++ b/src/projectile.c
@@ -61,7 +61,6 @@
 #include "mapgrid.h"
 
 #define	PROJ_MAX_PITCH			30
-#define	ACC_GRAVITY				1000
 #define	DIRECT_PROJ_SPEED		500
 #define VTOL_HITBOX_MODIFICATOR 100
 
@@ -918,6 +917,11 @@ static void proj_InFlightIndirectFunc(PROJECTILE *psProj)
 				psProj->startY + (distanceRatio * move.y),
 				psProj->srcHeight + move.z
 			};
+			if (nextPos.z > UWORD_MAX / 2)  /* Assume it wrapped around */
+			{
+				/* XXX FIXME Unfortunately, this usually occurs because we skipped past our target. */
+				nextPos.z = 0;
+			}
 
 			/* impact if about to go off map else update coordinates */
 			if (!worldOnMap(nextPos.x, nextPos.y))
diff --git a/src/projectile.h b/src/projectile.h
index 32636f8..2661200 100644
--- a/src/projectile.h
+++ b/src/projectile.h
@@ -42,6 +42,7 @@ extern	BASE_OBJECT	*g_pProjLastAttacker;	///< The last unit that did damage - us
 #define BURNING		0x02	///< Whether an object has just left the fire, but is still burning.
 #define BURN_TIME	10000	///< How long an object burns for after leaving a fire.
 #define BURN_DAMAGE	15	///< How much damaga a second an object takes when it is burning.
+#define ACC_GRAVITY	1000	///< Downward force against projectiles.
 
 /** How long to display a single electronic warfare shimmmer. */
 #define ELEC_DAMAGE_DURATION    (GAME_TICKS_PER_SEC/5)