By the time of the Vietnam conflict, aerial reconnaissance became much more sophisticated. Specially equipped airplanes carried a variety of cameras aloft to gather vital intelligence information. The venerable Canberra RB-57, the single-seat RF-101 Voodoo and the Phantom RF-4B&C's all played a vital role in support of military operations.

Your author flew 168 missions as navigator and systems operator in the back seat of RF-4C's during 1968-9, as a member of the 12th Tactical Reconnaissance Squadron. It was a fascinating assignment, despite being life-threatening and scary at times. Our missions usually supported Army operations. The nature of 'tactical' reconnaissance is one of immediacy. Field commanders needed information in a hurry. Our job was to provide it to them.

The RF-4C, twin-engine, two-seat jet fighter was used by the U.S. Air Force. It's RF-4B sibling was used by the Marines. Both were equipped with multiple cameras and other sensors.

Our high-resolution, side-looking radar provided intelligence experts with cloud-penetrating images of great value, though a complex post-flight processing method delayed availability. Radar data was not as quickly available as regular camera film.

RF-4C's also carried an infrared (IR) scanning system which was invaluable, especially for night operations. With it we could record images not perceivable with ordinary cameras. The IR scanner could detect small campfires hidden under the jungle foliage. It could even tell analysts about vehicles detected, such as whether or not the engine was hot or cold. A great deal of data could be gleaned from IR imagery. Unfortunately, IR was also a post-flight-processed data system, not as fast as visual photography.

We carried sophisticated oblique (side or forward looking) and vertical (down-looking) cameras with a variety of focal length lenses. One camera even scanned horizon to horizon, perpendicular to our flight path. Most-used were the latter two types. Miles and miles of film were expended to capture the images needed by Army commanders and staff analysts.

Photographic scale is important to users of film from our flights. Scale is the ratio between a distance on the ground to a distance on the image. It varies according to the focal length of the camera lens and the altitude of the airplane taking the pictures. The army wanted the largest scale they could get, an impossible one-to-one (1:1) scale would really please them.

With our 6-inch focal length vertical cameras, we often flew at low altitudes to get the best photographic scales. It was not uncommon to pass over our targets at 800 feet or less, day or night. That can be quite challenging at speeds of 500 knots in the rugged mountains, with the enemy using us for target practice. Low flight was also necessary to get below the clouds, so our cameras could 'see' targets.

Most photo reconnaissance missions were single ship, unescorted flights. Only when we were asked to get high priority targets in well-defended areas did we enjoy the luxury of fighter escorts to suppress enemy fire. Our RF-4C's were unarmed.

Our only defense against enemy attack was avoidance. If under attack from enemy planes, we turned tail and got away as fast as we could. If shot at by anti-aircraft guns or surface-to-air missiles, we used evasive maneuvers and highspeed to get away quickly. Sometimes we used electronic jamming equipment and expendable decoys, but our speed was our best defense. The RF-4C can really hustle when necessary. It is a Mach 2+ airplane.

More than half of the missions flown by your author were at night. In some ways they were safer than daytime missions, especially because small arms fire danger was reduced. But off-setting that was the greater difficulty of finding our targets in the darkness.

Many times our targets were merely a set of coordinates on a large-scale navigational chart. We were tasked to go out there and take photo's of what might look to some as just a grove of trees in a very large forest. From the air, at our speeds and in darkness, we could not see the confluence of jungle trails or small roads we might be seeking. Sometimes, we were sent to photograph river traffic or cargo transfer points used by the enemy. Most targets were nondescript and far from obvious to us.

On occasion, we were sent into a target area along with attack planes. We would go down to take pictures before the fighter-bombers did their thing. Then we would go in after them to take post-strike pictures. We joked that we were asked to do that just to see how angry the enemy was, after the attack planes were through. They were often "madder than hornets" and not bashful about showing it.

Our easiest missions, often used to indoctrinate crews new to the combat zone, were to get high altitude vertical photography of friendly installations. Both U.S. and South Vietnamese military sites were regularly photographed, usually with a single frame, small-scale picture. Several times a year we re-photographed these targets. I suspect that our images served a dual purpose. One was to enable local commanders to evaluate their changing perimeter defense needs. The other was to become a wall picture behind some officer's desk.

Navigation to targets was not easy, especially to find those nondescript jungle coordinates. Miles and miles of jungle all looks much the same. Few landmarks stand out to guide the flight crews. Time and heading was used, basic dead reckoning navigation. We approached our target from a known point, something as simple as a bend or fork in a stream, and flew a precise heading for a definite period of time. That usually took us right to our target. To allow for slight errors, we ran cameras for a few seconds before and after the expected time over target. The extra shots also helped the photo interpreters correlate film images with the terrain.

Night pictures required the use of photo-flash cartridges to illuminate the target. Making sure that a cartridge went off at precisely the right point was tricky. Usually, we'd use a few cartridges, three, five or even seven. The middle cartridge was intended to go off right over the target, with one, two or three before and after.

Fewer cartridges used were better than more. Enemy gunners could readily predict where you'd be after they saw you in the light of two or three. The more you use the easier it is for them to locate and shoot you. One defense, other than using the fewest number of flash cartridges, was to accelerate through the target area. That would make it harder for them to hit you, but it also spread out your cartridges. It was a trade-off.

The safest low-level night missions were those where only the IR system was employed. You did not leave a trail of illuminating flares. Your darkened airplane, zipping along at high speed, became very difficult for the enemy to see. Your only worry, aside from missing your target, was hitting something like a mountain or another darkened airplane.

One moonless night, while flying south at 500 feet along the Vietnam-Cambodia border, we scared the dickens out of ourselves and a flight of Army helicopters. We did not know they were there, nor they of us, as we flew right between a formation of six choppers. All of us were flying with lights out to avoid drawing enemy fire. It could have been a real disaster.

My experience in bombers, transports and a variety of training planes cannot compare to the exhilaration and challenge of tactical photo reconnaissance. Yes, it was dangerous, and sometimes it was mighty lonely going alone deep into enemy territory, but it was never dull.