ALTDEV.

Narrative

MY WIFE AND I HAD BEEN FLYING ALL DAY IN IMC CONDITIONS AND NOW AS WE NEARED OUR HOME BASE IN VERY CLR CONDITIONS; I HAD BEEN DIRECTED BY ZDV TO LEAVE OUR CRUISING ALT OF 12000 FT AND DSND TO 8000 FT IN PREPARATION FOR A HDOF TO DENVER APCH FOR VECTORS TO A LNDG AT APA. DURING THE DSCNT; MY WIFE; IN THE COPLT'S SEAT; BEGAN HAVING AN ALLERGY ATTACK AND REQUESTED HER MEDICINE FROM THE REAR SEATS. AS I TURNED TO REACH BACK FOR THE MEDICINE; I INADVERTENTLY DISCONNECTED THE AUTOPLT. I REACTIVATED THE AUTOPLT AND THEN IMMEDIATELY RETURNED TO SEARCHING FOR THE MEDICINE FOR AN INCREASINGLY AGITATED WIFE. IN MY HASTE TO HELP MY WIFE; I HAD NEGLECTED TO REACTIVATE THE DSCNT ALT WARNING SYS. WHILE CARING FOR MY WIFE AND HER ALLERGY ATTACK; I WAS SUBCONSCIOUSLY RELYING ON THE ALT WARNING SYS TO ADVISE ME OF THE ASSIGNED LOWER ALT. THE CAVU WX CONDITIONS FURTHER SERVED TO EASE MY CONCERN FOR THE READILY- VISIBLE; FLAT TERRAIN BELOW. THE CTLR THEN SAID HE SHOWED ME 700 FT BELOW MY ASSIGNED ALT. I IMMEDIATELY CORRECTED ALT AND WAS THEN HANDED OFF TO DENVER APCH. THE EVENT OCCURRED OVER A VAST; FLAT; DESERTED; DRY-LAND RANCHING AREA WITH A GND ELEVATION OF ABOUT 5200 FT. THERE WAS NO OTHER ACFT TFC IN THE AREA NOR RANCH BUILDINGS OR COWS ON THE GND. LESSON LEARNED: EVEN WHEN FLYING IN THE COMPANY OF A DISTRAUGHT AND MEDICALLY NEEDY WIFE; THE PLT MUST ALWAYS FIRST FLY THE AIRPLANE.