So, here were we are one cold February day in Colorado. Our mission was to accomplish a practice annual instrument check for one of the pilots assigned to ADCOM (Air Defense Command) Headquarters in down town Colorado Springs at Ent Air Force Base (now the United States Olympic Training Facility). These headquarters peuks, as we affectionately called them, and they called themselves, were desk jockeys with flying slots. So, they had the same training squares and check ride requirements as we did in the flying squadron. They spent most of their time pushing desk drawers and were therefore less proficient than us regular squadron guys.
I was a fairly new qualified IP (Instructor Pilot) in the T-33 and drew the practice instrument check duty for this sortie. As such, I would sit in the front seat, do the start, taxi, and take off. At some point after takeoff, he would pull the instrument hood from its stowed position behind his seat, extend it over his head forward to the top edge of his rear cockpit instrument panel and snap it in place. This would completely block the outside world and “encourage” him to fly solely on instruments. This is exactly how he would fly his instrument check ride with the SEFE (Standardization Evaluation Flight Examiner). In this picture, the “bag” (instrument flying hood) can be seen in it’s stowed position at the back of the canopy.
(https://i.postimg.cc/fRnv3tkm/24605-C0-F-3-DA8-457-B-9047-4-AC732-F13-AC8.jpg) (https://postimages.org/)free screen capture software (https://postimages.org/app)
We would fly the short distance to Buckley ANG (Air National Guard) Base on the southeast side of Denver to shoot various instrument approaches. Buckley had a good variety of different instrument approaches and made for a good work out for the guy under the hood.
As we departed Colorado Springs, the weather was 8-10,000 feet overcast with light winds. A fairly typical winter day. The forecast was for a winter storm front to move in late in the day, well after our morning flight.
After taxi and take off, I checked in with the radar departure controller and he vectored us toward Buckley. My “victim” voluntarily decided it was time to get under the hood. When he told me the hood was in place, we transferred aircraft control as pre briefed. My job from here on was to monitor his performance, clear for other traffic, communicate with the air traffic controllers, and throw in tidbits from my vast knowledge base as a First Lieutenant Instructor Pilot. My “victim” was an old head, crusty Major with a ton of experience in ADCOM and was previously an F-106 pilot. He had easily forgotten ten times more about flying than I had amassed in my whole 24 years of life. This was a great opportunity for me to watch and learn from a master.
We were vectored into the instrument approach pattern at Buckley and promptly got at it. The Major flew a nice first approach, executed the published missed approach procedure, climbed up to the assigned traffic pattern altitude, and got ready for a different type of instrument approach. At this point we would transfer aircraft control, I would fly for a few minutes to give him a break, and time to get the next instrument approach “plate” displayed and ready. The instrument approach plates were in a small book with various approaches for airports all over the continental US and Canada. An example of an instrument approach plate at Buckley:
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We continue flying around the instrument pattern doing different approaches. He’s doing well and the air is smooth, until the third approach. The clouds are starting to cover the mountains west of Denver, it’s starting to get a bit bumpy, and the surface winds at Buckley are starting to increase and get gusty. We’ve got plenty of gas and didn’t plan for an alternate due to the good weather at the Springs and the “forecast” through the afternoon hours. Even if the weather came down rapidly we could get back to the Springs and Pueblo was a short flight to the south. It was clear and calm in Pueblo.
Then it starts spitting rain that was sort of sticking to my windshield. As he’s flying the next approach, totally oblivious to what’s going on outside, the ceiling is dropping, it’s getting bumpier, and we are starting to pick up some very light ice. The picture out toward the mountains is less than inviting. I can see the cloud deck rolling over the crest of the Rockies and down the valleys to the east.
The T-33 was able to to accumulate a fair amount of ice and continue flight safely. But, we were accumulating ice rapidly. The wing tip tanks had a white cap of ice which was more visible because of the flat black paint on the inner side of the tanks. The wings quickly went from a thin coat of shiny ice to a rough texture. On the nose in front of me was a flat blade UHF radio antenna. It had gone from its normal shark fin appearance to a rough, rounded, softball sized appearance. This all occurred during the short span of the final portion of the instrument approach. In the back, he was fighting to maintain the approach criteria, not uncommon in bad weather. But this was his sixth approach and he was getting tired.
We went missed approach and I asked the approach controller for vectors back to the Springs. We transferred control of the jet so I could fly and let him rest, with the plan for him to fly the approach into the Springs where we would land and call it a day. Enroute to the Springs, I dialed in ATIS (Automatic Terminal Information Service) which continuously broadcasts the current, or updated weather over a dedicated frequency for the airport. Our 8-10,000 foot overcast was now 800 feet overcast with strong gusty winds out of the south and snow flurries west and northwest. Upon hearing this, the Major says, “OH NO, NOT THAT DAMN DME ARC TO THE BACK COURSE ILS!” Back then, the back course ILS was the only approach to the south on the single runway at Colorado Springs. Because of the rapidly rising terrain of the Black Forrest to the north, there was a curving DME (Distance Measuring Equipment) arc from the east that brought aircraft around to the final approach course for landing to the south. Although the plate depicted below is for an ILS, back in the day it was a Back Course Localizer. This plate gives you an idea of the DME arc and associated high terrain to the north.
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This was truly the most hated and dreaded instrument approach in all of the airports in the US and Canada.
Because of the T-33’s very antiquated instrument equipment, this was a very difficult approach to fly even in the best of conditions. The Major was not at all looking forward to flying this approach. It was understandable because of his proficiency level in the jet due to his staff peuk job. I, on the other hand, had flown this dreaded approach dozens of times and was relatively comfortable with it. Not a favorite, but doable. I told him to relax, stow the bag, and I would fly the approach. We’re now in the weather, accumulating even more ice, but the T-bird was stable, with power settings normal for the airspeed, and flying as well as could be expected in the now constant turbulence.
We are vectored to the IAF ( Initial Approach Fix), the beginning of the full approach procedure, and beginning of the dreaded DME arc. The weather is getting progressively worse and the ice is still accumulating. The blade antenna on the nose in front of me now looks more like a grapefruit. The leading edges of the tips tanks are now solid white. The leading edges of the wings looked pretty ugly and I quit checking them. My inner being thought of “It would be a good idea to add about 20 knots to the computed normal approach speed to compensate for the ice” seems like a good idea. I agreed with myself and did so after configuring for landing. We worked our way around the DME arc and intercepted the final approach course for runway 17 at the Springs.
The final approach required a couple of altitude step downs for terrain clearance. We accomplished those and should be breaking out of the ATIS reported weather ceiling. Still in the thick of it, I’m mentally preparing for a missed approach and diversion to Pueblo about 20 minutes south. We break out of the weather at about 600 feet. I’m carrying 20 knots of extra airspeed and fly to the runway a little lower than normal for some extra safety factor, and start slowly reducing power. The ice bound T-33 was done! With that initial power reduction and resulting airspeed reduction, it completely dropped out of the sky that last few inches to the runway. As I’m keeping the jet tracking straight on the now icing up runway with gusty south to southwest winds, the thought that maybe 20 knots extra wasn’t enough, came to mind.
We taxied in and parked on the ramp at our assigned spot. As the crew chief parked and chocked us, surrounding crew chiefs, and maintenance guys started surrounding our “Ice Bird”.
We shut down, safetied the ejection seats, and climbed down. The ice accumulation was far worse than I realized. Everything front facing had a thick coat of clear and rhime ice. The landing gear were so iced up, it was doubtful they would have retracted if we went missed approach. The engine inlets had so much ice, the openings were about half normal size. The engine was equipped with a FOD (Foreign Object Damage) screen in front to prevent stuff off the ramp, birds during flight, etc from going down the turbine section and causing a bad day. The screen was like super chicken fence in appearance. The normally large squares in the screen were reduced to the diameter of a finger nail. Behind the cockpit, on the back of the fuselage, were a pair of long rectangular plenum chamber doors. The purpose of these doors was to provide additional cooling for the engine during ground ops. On the ground, the doors would automatically open via suction and intake additional air to the engine. Those guys at Lockheed were quite clever. Anyhow, the plenum chamber doors were both frozen open with ice. No telling how long they were like that during flight.
The assembled crowd started chipping at the ice with screw drivers and hammers to no avail. The ice was too thick, the temperature had fallen below freezing, and it was now snowing.
Note to young 1st Lieutenant Instructor Pilot self: “You should have RTBed (Return To Base) at the first indication of ice and rapidly failing weather forecast. DO NOT DO THAT AGAIN. We can always schedule another practice ride for the headquarters peuk.”
An interesting bit of aviation trivia that I learned later in the F-106: At 400 knots and above the skin temperature caused by air flow friction prevents ice from accumulating.
That, of course, didn’t apply in the T-33.
“God looks after fools and fighter pilots”.
Just ran across this picture of a taxiing T-33 with the plenum chambers doors suctioned open. Although only one is visible in the photo, there is another on the other side of the fuselage centerline.
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.....and see the “One Star” emblem on dark background on the vertical fin? At the Springs, anytime an O-6 or above flew, maintenance would remove the plain aluminum plate and replace it with the appropriate rank. My 1st Lt bud and I took exception to that since we were always out cross country. So, our crew chiefs presented us with a dark blue plate with a silver 1st Lt bar the next time we showed up for a cross country.
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