The Fliegerfaust Roars Back To Life After 77 Years

March 9, 2022 by Tom Nardi 36 Comments

As their prospects for victory in the Second World War became increasingly grim, the Germans developed a wide array of outlandish “Wonder Weapons” that they hoped would help turn the tide of the war. While these Wunderwaffe obviously weren’t enough to secure victory against the Allies, many of them represented the absolute state-of-the-art in weapons development, and in several cases ended up being important technological milestones. Others faded away into obscurity, sometimes with little more then anecdotal evidence to prove they ever even existed.

One of these forgotten inventions is the Fliegerfaust, a portable multi-barrel rocket rocket launcher designed for use against low-flying attack planes. Although thousands were ordered to defend Berlin in 1945, fewer than 100 were ever produced, and there’s some debate about how many actually survived the war. But that didn’t stop [Jonathan Wild] of Wild Arms Research & Development from building a functional replica of the weapon based on contemporary documentation and blueprints.

Building the launcher was relatively straightforward, as it’s little more than nine tubes bundled together with a handle and a simplistic electric igniter. The trick is in the 20 mm (0.78 inch) rockets themselves, which are spin stabilized by the exhaust gasses exiting the four angled holes on the rear. With no fins or active guidance the path of each rocket is somewhat unpredictable, but this was known to be true of the original as well.

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Mystery WWII Navy Gear With Magic Eye

January 28, 2022 by Chris Lott 34 Comments

There’s an unknown piece of military electronic gear being investigated over on [Usagi Electric]’s YouTube channel (see video below the break). The few markings and labels on the box aren’t terribly helpful, but along with the construction and parts, seem to identify it as relating to the US Navy from the WWII era. Its central feature is a seeing-eye tube and an adjustment knob. [David] does a bit of reverse engineering on the circuit, and is able to fire it up and get it working, magic eye squinting and all.

But there’s still the unanswered question, what was this thing supposed to do? Besides power, it only has one input signal. There are no outputs, except the “data” presented visually by the magic eye tube. Commenters have suggested it was used with sonar equipment, calibration tool, RTTY tuning aid, light exposure meter, etc. But if you dust off your copy of Navships 900,017 “Radar Systems Fundamentals” from 1944 and turn to page 249, there’s a section entitled Tuning Indicator that describes this circuit, almost.

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Despite Uncertainty, WWII Warbirds Resume Tours

June 28, 2021 by Tom Nardi 26 Comments

Back in September of 2019, I had the opportunity to climb aboard the restored B-17G bomber Nine-O-Nine as part of a national “Wings of Freedom” airport tour operated by the Collings Foundation. I was excited to get up close and personal with such an iconic aircraft, particularity since Hackaday gave me a platform to share the experience with a global audience. With fewer than 50 B-17s left in the world, and most of those in the United States, taking this sort of “virtual tour” was as close as most people would ever get to seeing what it was really like for the crews who operated these machines over the skies of Europe more than 75 years ago.

Tragically, just a week after the article was published, the Nine-O-Nine crashed during a visit to Bradley International Airport in Connecticut. The pilot, co-pilot, and five paying passengers were all killed in either the initial impact or the subsequent fire. When crews were finally able to extinguish the flames, the left wing and tail were all that remained of the once mighty bomber. In a twist of fate, some of the images I took for the Hackaday article ended up being included in the National Transportation Safety Board (NTSB) accident report, as they represented perhaps the most detailed photographic record of the aircraft’s condition before the crash.

In the weeks and months that followed, many voiced their concerns over what the Federal Aviation Administration (FAA) calls “Living History Flight Experience” aircraft such as those operated by the Collings Foundation. The main point of contention was whether or not these planes were too old to safely carry passengers, and by extension, whether continuing to fly them around the country presented a menace to the national airspace. Critics argued that whatever cultural benefit offered by the chance for the public to tour or ride these antique aircraft was not worth anyone losing their lives over; a line of logic that’s difficult to find fault in.

Then came COVID-19. By March of 2020, individual states had already started going into lockdown, and suddenly there were far more pressing matters to address than the fate of a few dozen teetering WWII aircraft. It was around this time that the FAA pulled the Collings Foundation’s license to conduct any more paid flights, but since outdoor gatherings such as airshows were being put on hold for the foreseeable future, the measure had little immediate impact. It was clear these airborne museum pieces were going to spend most of 2020 in their hangers anyway.

Now, thankfully, the pall of COVID-19 is finally beginning to lift over the United States. In response to widespread vaccine availability, most states are ending or at least reducing their restrictions on outdoor events. With major airshows like the “World War II Weekend” in Reading, Pennsylvania given the green light to proceed, these legendary aircraft are being awakened from their long slumber and making their first tentative flights of the post-pandemic era.

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Wooden Tank’s Movement Hinges On Hinges

September 9, 2020 by Brian McEvoy 28 Comments

When we first looked at this tank, we thought it was pretty cool. The sides are unpainted 1/2″ (12mm) plywood, so it is not flashy. The dimensions came from Google-fu-ing the heck out of the WWII Hetzer and scaling them to 1:6. What knocks our socks off is how much [Bret Tallent] made use of parts you would find in a hardware store or bicycle shop. He uses twin motors from electric bikes, and the wheels look like replacement shopping cart wheels. The best part is the treads, which are dozens of hinges fastened with pairs of bolts and nylon-insert nuts. Something is reassuring about knowing that a repair to your baby is no further than a bike ride.

We don’t know what started [Bret] on his path to sidewalk superiority, but we suspect he is cooped up like the rest of us and looking to express himself. Mini-Hetzer is not licensed by Power Wheels and never will be, so it probably won’t turn into a business anytime soon. There is a complete gallery starting with an empty plywood base, and the pictures tell the story of how this yard Jäger got to this point. There are plans to add a paintball gun and streaming video, so we’d advise that you don’t mess with the jack-o-lanterns on his block this year. Give his gallery a view and see if you don’t become inspired to cobble something clever from the hardware store too. Then, tell us about it.

Another creative hacker used wood for their tank body and the treads as well. If you like your treaded vehicles functional, we have one meant to taxi small planes over the tarmac.

World’s Only Flying Twin Mustang Goes On Sale

September 3, 2020 by Tom Nardi 18 Comments

Given the incredible success of the P-51 Mustang during the Second World War, it’s perhaps no surprise that the United States entertained the idea of combining two of the iconic fighters on the same wing to create a long-range fighter that could escort bombers into Japan. But the war ended before the F-82 “Twin Mustang” became operational, and the advent of jet fighters ultimately made the idea obsolete. Just five examples of this unique piece of history are known to exist, and the only one in airworthy condition can now be yours.

Assuming you’ve got $12 million laying around, anyway. Even for a flyable WWII fighter, that’s a record setting price tag. But on the other hand, you’d certainly be getting your money’s worth. It took over a decade for legendary restoration expert [Tom Reilly] and his team to piece the plane, which is actually a prototype XP-82 variant, together from junkyard finds. Even then, many of the parts necessary to get this one-of-a-kind aircraft back in the sky simply no longer existed. The team had to turn to modern techniques like CNC machining and additive manufacturing to produce the necessary components, in some cases literally mirroring the design in software so it could be produced in left and right hand versions.

Recovering half of the Twin Mustang in 2008.

We first covered this incredible restoration project back in 2018, before the reborn XP-82 had actually taken its first flight. Since then the plane has gone on to delight crowds with the sound of two counter-rotating Merlin V-12 engines and win several awards at the Oshkosh airshow. The listing for the aircraft indicates it only has 25 hours on the clock, but given its rarity, we can’t blame [Tom] and his crew for keeping the joyrides to a minimum.

As important as it is to make sure these incredible pieces of engineering aren’t lost to history, the recent crash of the B-17G Nine-O-Nine was a heartbreaking reminder that there’s an inherent element of risk to flying these 70+ year old aircraft. A world-class restoration and newly manufactured parts doesn’t remove the possibility of human error or freak weather. While we’d love to see and hear this beauty taxiing around our local airport, it’s a warbird that should probably stay safely in the roost. Hopefully the $12 million price tag will insure whoever takes ownership of the world’s only flying F-82 treats it with the respect it’s due.

The Mark 14 Torpedo — When Just About Everything Goes Wrong, Even The Testing

May 13, 2020 by Al Williams 70 Comments

I am a fan of the saying that those who don’t know history are doomed to repeat it. After all, humans have been building things for a number of centuries and we should learn from the engineers of the past. While you can learn a lot studying successes, sometimes — maybe even most of the time — we learn more from studying failure. The US Navy’s Mark 14 torpedo certainly has a lot to teach us.

The start of the story was the WWI-era Mark 10 torpedo which was fine for its day, but with faster destroyers and some additional data about how to best sink enemy ships it seemed necessary to build a new torpedo that would be faster, carry more explosive charge, and use a new method of detonation. Work started in 1931 with a $143,000 budget which may sound laughable today, but that was a lot of coin in the 1930s. Adjusted for inflation, that’s about $2.5 million.

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Poor Maintenance Could Have Led To Fatal B-17 Crash

March 28, 2020 by Tom Nardi 49 Comments

In October the Nine-O-Nine, a fully restored Boeing B-17G bomber owned and operated by the Collings Foundation, crashed with thirteen people on board. After landing hard and skidding into the de-icing tanks at the Bradley International Airport, all but the tail and port wing of the 74 year old WWII aircraft was destroyed. Seven lives were lost in the accident, including that of Pilot Ernest “Mac” McCauley, who was regarded as one of the most experienced B-17 pilots in the world.

While the National Transportation Safety Board (NTSB) investigation is still ongoing and hasn’t made a final determination as to what ultimately brought down the Nine-O-Nine, enough serious maintenance issues were uncovered while examining the wreckage that the Federal Aviation Administration (FAA) has decided to rescind the Collings Foundation’s license to conduct any more paid flights on their remaining WWII aircraft. While many have spoken out in support of these “living history” flights, the FAA says they must be conducted in such a way that they don’t hinder the safety of other air traffic.

With the vast majority of the B-17’s airframe gone, the NTSB investigation has focused on the four 1,200 horsepower Wright R-1820 “Cyclone” engines recovered from the crash site. Investigators found that hastily attempted repairs to engine number 4, which is believed to have failed in-flight, were actually hindering normal operation:

Regarding engine 4, to prevent the magneto “P” leads from separating from the
magnetos, someone had attempted to rig the magneto leads in place with safety wire.

Inspection and testing of engine 4 left magneto revealed the movement of the safety-wired lead caused grounding to the case, which rendered the magneto lead inoperative.

Further, all of the spark plugs in the number 3 and 4 engines were found to be fouled and had electrode gaps that were out of tolerance. From an examination of the aircraft’s maintenance records, it was also learned that an arcing and burned wire had been replaced without any investigative steps taken to find what caused the failure to begin with.

With basic maintenance tasks either not being performed or at least done incorrectly, the FAA has called into question the culture of safety at the Collings Foundation. The paper is careful not to directly accuse the Foundation or any of its staff with outright negligence, but the implication seems clear.

The loss of Nine-O-Nine hit especially close to home for Hackaday. Just a month prior to the crash we had the opportunity to tour the aircraft, and came away with a newfound respect for not only those who designed and built the iconic bomber but the brave young men who flew it. Losing such a rare and historically significant aircraft and its crew was already a tragedy, but to find that negligence may be to blame is truly inexcusable.