MiG-23 Twilight Afterburner Run

On Saturday the Cold War Air Museum performed a twilight taxi test of its MiG-23UB "Flogger" aircraft.

The following photographs are provided courtesy of Ivan Voukadinov, who made the trip from Chicago for the event. Ivan is from Bulgaria, where his uncle was a Bulgarian Air Force pilot who flew our Bord 022 during its military career.

Photographers and movie makers refer to the time that straddles sunrise and sunset as "Golden Hour" because the natural lighting has a certain glow to it.

15 minutes after sunset, the MiG-23 was taxied into position on the runway and the afterburner was lit for approximately 3.5 seconds. The initial afterburner ignition is the most impressive because of the sheer volume of raw fuel that is sprayed into the tail pipe. The MiG-23 consumes approximately 2 gallons of Jet-A per second at max afterburner.

After slowing down and leaving the runway, the wings were swept to the 72° position, giving the Flogger its signature "go fast" look.

The MiG-23's appearance is even more menacing after dark. Taxi lighting consists of illumination on both sides of the aircraft. The landing configuration consists of illuminating only the larger light on the port side of the aircraft as Soviet pilots were taught to "look left" during landing.

The MiG-23 was the first Soviet design that took cockpit ergonomics into strong consideration and the internal lighting is particularly well thought out.

Even sitting still the MiG-23 looks like it's going Mach 2.35.

Many thanks to Ivan and all the other photographers who made it out to the museum!

June 25th, Airport Day

The Airport where the Cold War Air Museum is located hosted another community event last Saturday. More activities and events attract more visitors and we are happy to see them.

Our volunteers rolled out a number of aircraft for viewing.

And other aircraft from the CAF were put on display as well.

Quite a few aircraft flew in. This demonstration team of RV's showed their skill in formation exercises.

The Mi-24 is passing well behind the parked RV's, making it look much smaller than it does up close.

And the MiG-23 was on display as well.

Jon said it was a good day to make MiG noise.

(Jon likes to make MiG noise)

And the MiG is very good at making noise.

Add fuel - Make noise.

Make lots of noise, is good, is normal.

MiG-23 Progress

One of the more interesting components of the MiG-23 is the PGL-30M Hydraulic Powered Speed Regulator, a device that uses fuel to feed a vaned drive which in turn powers the AC generator.

Rather than using a complicated gear reduction mechanism to drive the AC generator from the engine rotation, the designers at MiG decided to use fuel pressure through a fluid labyrinth to obtain the constant RPM needed by the AC generator.

This works beautifully, producing a constant (plus or minus 2%) RPM... except when the PGL-30M leaks. Of course, when it leaks, it leaks fuel, which is the case with the Cold War Air Museum's MiG-23.

The MiG-23 doesn't do anything in a small way when it comes to fuel. Until the device was removed it was necessary to put a 150 gallon plastic stock tank under the aircraft to catch the drip.

Here Jon holds the leaking PGL-30M, the grimace on his face evidence of the fact that the device is even heavier than it looks.

The museum has located a replacement regulator, which we expect to be arriving in the near future.

MiG Manuals

One of the goals of the Cold War Air Museum is the restoration of Eastern Block aircraft.

We are fortunate that the Soviets distributed their maintenance manuals all over the world along with their equipment. The Soviet designers also helped our cause tremendously by using (in general), proven and robust designs. Many of the parts in each of these aircraft are often found in other aircraft as well.

This is a sample from some of the multiple cases of manuals that various associates have purchased from around the world. Location diagrams like these help generate a mental picture of the inside of the aircraft, where parts are located and how they connect together.

Identifiers on the equipment diagrams help direct technicians to specific sections as necessary.

We are glad that the Soviets relied on "old fashioned" paper products for this material. No computer or microfiche reader necessary and the technical language is straightforward to translate.

MiG-23 Work Resumes

Work has resumed on the Cold War Air Museum's MiG-23UB.

As readers of this blog may know, the Flogger developed a mysterious fuel system leak after ground test in the spring. Replacement parts have now arrived allowing us to resume.

Here are a few photos of the inspection work:

With some clever modification a MiG-23 engine dolly can be made to work as a MiG-23 tail dolly. We were able to pull the tail back to expose inner connections of the single-point fuel port. Interestingly, a US/NATO single-point connection fits perfectly on the Soviet aircraft.

Initially we put 25 liters of fuel into the single-point connection and got 20 liters on the floor. With some fixing, we put 125 liters in and got only 0.5 liters to leak out. Hopefully with some new o-rings the leak will be completely fixed.

The museum's goal is to have the MiG-23 ready for more ground testing, including a test of the afterburner, some time this month.

MiG-23 Dorsal Repair

When the Cold War Air Museum MiG-23 was shipped to Texas,

it came partially disassembled in an open top container.

A portion of the structure on top of the aircraft obviously encountered something along the way. Fortunately, the extent of the damage was very small compared to the mishap that destroyed one of our Mi-24's.

As work has progressed on the MiG, the damaged ribs and damaged portion of the turtledeck skin were removed.

Replacement ribs were fabricated and a replacement piece of skin was flush joined to the remaining structure.

The final join will be a perfect fit. We are fortunate to have a craftsman with the ability to do the necessary work.

MiGs and Mils, Cockpit Color

A topic of discussion for visitors at the Cold War Air Museum has been; "What color is that?" Or; "Why did the Soviets paint their cockpits green?"

Model making web sites have frequent questions and discussions about getting the exact color of soviet aircraft cockpits, exactly right.

Fortunately, we have the advantage of having the "real thing" with which to compare. We have been told that the color chosen by Soviet designers helps to reduce stress and maintain a pilot's effectiveness on long missions. While the Soviets were not the only country (or manufacturer) to use this color, they have used it for so long and in such great numbers that it has become a trademark of Sov-block aircraft.

Because not all aircraft are painted at the same time, or at the same place, there is some inevitable variation in color. Some aircraft have more of a green tone.

And, some have more of a blue tone, even when the aircraft come out of the same factory in the same country. In general though, the description "blue-green" seems to fit slightly more of the aircraft we see (especially the newer ones), than the alternate description often given as "light green".

These three panels, or sections of panels from different aircraft, show some color variation even though all three came from the same factory.

We don't worry too much about making an exact color match to some mythical factory standard, but we do make a color match for individual aircraft when necessary during restoration. Besides, we are mostly guys, and most of us simply made it through kindergarten with the 8-count box of crayolas, not the 64 count box (I don't even know how they come up with the names for so many colors). While the paint store most closely matched the blue-green above with a commercial color named "Mermaid Green", it's just not right to say "Our fighter cockpits are decorated in Mermaid Green". So for now, we'll just stick with something that fits within our limited repertoire and continue to refer to all of these colors as simply blue-green, or more simply as just that "Russian Cockpit Color".

Another "Big Iron" Saturday at the Cold War Air Museum,

We consider ourselves lucky when Mother Nature cooperates with Cold War Air Museum central planning.

Last Saturday, the weather turned clear and warmer so we were happy to bring some of our aircraft out for display and flight.

One of our associates, a former Russian Major checks the line. Later he assisted Jon with taxi and systems checks in the MiG-23 and went for a flight in one of the L-39s.

A view through the window from the Mi-2 shows the MiG-23 and the Mi-24 from a different angle.

We had a number of visitors over the weekend who took advantage of the beautiful weather and Miguel came by with some of his delightful models for more photo updates. We are looking forward, as always, to his newest work appearing on his Flickr pages.

Unfortunately, we are about to enter another cycle of cold and rain, forcing us back to work inside. Perhaps we will be able to report additional progress on some of our many projects by next weekend.

Anatomy of a MiG-23 Caution and Warning Panel

While the original Cyrillic Russian in the MiG-23's cockpit is authentic, if a red light comes on in the cockpit, we'd like it to come on in English. Labeling and placarding the cockpit for safety, and changing the altimeter from meters to feet are some of the steps necessary before we can fly the aircraft in U.S. Airspace.

The MiG-23 is part of the first generation of Soviet aircraft where cockpit ergonomics were given major consideration in the design. The layout is clean and logical but at the cost of increased complexity of the mechanical "switchology".

Like the rest of the MiG-23, the Caution and Warning panels are rugged and well thought out. The main panel shown here can be removed with a single screw, making it easy to change the 28v light bulbs behind it. The "day/night" knob adjusts the brightness of the lights and doubles as a "push to test" button that illuminates all bulbs so the pilot can check if they're burned out.

Here the panel is seen from the back with encapsulation for each light bulb so that there is no "light bleed" from one indicator to the next. The brightness adjustment knob carries through the "push to test" action to a button behind the panel. A spring returns the knob to its normal position.

The panel is continuously adjustable from fully bright "day" mode to a very dim "night" mode. Unusually, this is done with a mechanical slider that blocks the amount of light coming to the panel rather than by regulation of the voltage intensity being applied to the lights.

The slider is shown in this photo in both the fully open and fully closed positions.

The first step to converting the panel to English is to document the existing panel both for the museum's records and to facilitate translation to English terms that are familiar to pilots.

There are two primary panels, one dealing with engine issues and one primarily dealing with the six fuel tanks (plus external drop tanks) that are automatically managed for the pilot. Additionally, a panel of "trim neutral" green lights and a set of information lights on the gear tree need to be translated.

The MiG-23's unique "swing wing" design is brought up on the panel's "SPREAD WINGS" light. As it is virtually impossible to land the MiG-23 with the wings swept to any degree at all this light exists to alert pilots to the danger that the gear have been lowered and the wings are not in the full forward position.

The designers at MiG chose a panel construction that easily lends itself to conversion to English while retaining the "feel" of the original panel.

Each indicator consists of a seven-layer sandwich of frosted tiles, the label with the wording on a thin "film", copper gaskets to provide a snug (vibration proof) fit, and a glass "color" tile that is red, yellow, or green as relates to the urgency of the information being provided to the pilot. Red tiles illuminate for emergency situations (fire, loss of an electric generator, or very low fuel state), yellow for situations needing the pilot's attention (hydraulic system anomalies), and green for information not requiring action (such as when a fuel tank reaches an empty state).

Additionally a master caution annunciator and two red master caution lights are placed in the pilot's "heads up" field of view. The blinking of the master caution system can be canceled by pressing the master caution annunicator light/button.

After some discussion on translation, a final panel is created with Inkscape for laser printing on transparency film. Here Jon is shown with the translated film and scissors on the, "You want to fly it, you cut them out!" plan.

MiG-23 Tire Change

Following the taxi test of the MiG-23 at the Cold War Air Museum during Soviet Big-Iron Saturday, we began noticing that the port tire was losing pressure. We had anticipated replacing the tires that came with Bord 022 and fortunately, our replacement set was already on hand.

A particularly handy thing is to keep a spare tire already mounted on a spare rim to minimize the time needed to "rescue" an aircraft in case a tire should "blow", or go flat during operations. One of our "spares" was already mounted on a rim, simplifying this replacement process.

However, this did not eliminate the need to read the instructions. The MiG-23 wheel assembly consists of approximately 60 individual components, not including nuts and washers (so much for Soviet Simplicity, this time anyway). Here Jon is seen trying to figure out what does and, more importantly, does not need to be taken apart in order to replace the wheel.

The massive disk brake mechanism incorporates an anti-skid system and uses six big rotors and seven heavy-duty stators in each wheel.

The amount of heat that can be generated by the brakes poses a serious bursting issue with the tires. To prevent this, the designers at MiG incorporated two interesting features. The first is an electric fan. Mounted in the center of the axle, the fan activates when the "weight on wheels" switch signals that the aircraft is once again on the ground.

Shown with the axle fan is the nut that holds the wheel on. A keeper ring goes between the fan mounting bolts and the axle to keep the fan and the nut from turning as the tire turns. In the picture below, Jon is inspecting the electrical connection for the fan motor in the center axle.

The second feature is a solder plug that melts at 140°C, allowing pressure to escape before the tire can burst. On fast landings or after any extensive brake use, MiG-23 pilots may alert their ground crews so the wheels can be doused with water so the plug doesn't melt.

Sliding the tire on over the six rows of rotors is a little like working a combination lock, but with a little light on the subject and some patience, Jon and Sean were able to get the tire on fairly easily.

All that remains is re-mounting the mud guard, applying safety wire and cotter pins to various keepers, and... of course... next, the replacment of the starboard tire.

More Miguel's MiG Models

Miguel, photographer and museum associate, has used the aircraft at the Cold War Air Museum as a backdrop for his work before. Our cold war era aircraft, equipment and uniforms help accent his work.

This Saturday he photographed Sarah, a professional model from the DFW area who was excited to augment her portfolio with something more unusual.

 

The weather was freezing, the wind was blowing, but Sarah was a real trooper. Here she is posing with one of the museum's L-39s in a cold war era uniform.

Always the professional, it's hard to tell from this photograph that she was mere moments away from becoming an ice sculpture.

Inside, Sean and Rene were able to locate some heaters and Miguel got these terrific shots with the Mi-2 helicopter and MiG-23 supersonic interceptor.

  

As the MiG is undergoing restoration it was possible to put Sarah in the front seat of the Sparka and let her light up the caution and warning panel without fear of her setting off the pyrotechnic charges that would normally be part of the ejection seat. The result was this very unusual photo of Sarah and the "christMiG tree" lights.

Our thanks once again to Miguel for letting us use some of his photos on the blog. A larger collection of photos can be found on his Flickr page.