Online Extras

E-mail Article to a FriendPrint ArticleBookmark and Share

The rapid rise and fall of the Bachem Ba 349 Natter (Viper)

Free online extra
By Mat Irvine
In the December 2008 FSM, Mat Irvine shows you how to build a base for the Ba 349 Natter. The following essay is exclusive to FineScale.com.

As World War II progressed and air supremacy slipped away from the Luftwaffe, Germany was increasingly eager for new, even unorthodox weapons to stem the Allied onslaught. One of these would have been the Bachem Ba 349 Natter (Viper), a vertical-takeoff, rocket-powered interceptor intended to attack the relentless streams of Allied bombers pounding Germany daily.

The Natter was the brainchild of master engineer Erich Bachem, who, like many German aeronautic designers, entered aviation through building wooden gliders (Germany having been banned from building powered aircraft after World War I). Bachem became technical director at Fieseler, where he co-designed the short-takeoff-and-landing Fi 156 Storch in 1935. In 1942, he set up his own company, Bachem-Werke GmbH, which fabricated structures from wood and metal, in the town of Waldsee in southwestern Germany. It was here in 1944 that he drew up initial plans for a formed-wood rocket plane - the Natter.
The Ba 349 was to launch vertically and climb at high speed to its attack altitude, at which point the pilot assumed control of the craft and guided it toward the approaching bomber formation. After firing a salvo of 24 Föhn 73mm rockets (each armed with nearly a pound of explosive), the pilot would descend and slow the craft to about 150 mph, get out of his flight harness, and jettison the forward part of the aircraft, initiating a sequence in which a parachute attached to the rear section would deploy, carrying the valuable rocket engine back to earth for recovery. The sudden aerodynamic drag would pull the craft from behind the pilot, who would then descend by parachute to fight another day.

Chief among reasons for this "landing" method were: 1) Like the Me 163 Komet, the Natter was powered by a Walter HWK 109-509 rocket motor using highly unstable C-Stoff/T-Stoff fuel that could (and would) spontaneously explode given the least opportunity, such as a landing. 2) Pilots would not have to be trained to land the craft (or take off, for that matter) - and experienced pilots were increasingly scarce in Germany's losing battle with Allied air forces.
Initial tests produced hopeful results. Towed aloft by a Heinkel He 111 and released, the Natter flew reasonably well in horizontal flight. After the prototype launch tower was built (in a desolate, flat area called Ochsenkoft on the Heuberg, on the Baden Plateau in southwest Germany near the Danube River), unmanned vertical launches also went reasonably to plan.

The prototype launch tower was a 65-foot tall metal framework (far more substantial than the "telegraph pole" launchers proposed for operational use). The tower could rotate 360 degrees and tilt as well. However, these features were never used for any launch - the Natter just went straight up!

Numbers vary, but it appears there were some 34 Natters built, including glider versions with fixed undercarriage, test versions never intended to fly, and the ones that were indeed launched vertically.
The first successful vertically launched Natter was numbered M16 (an earlier, failed attempt was M21 - the numbers were not always sequential). The color of M16 was a drab ivory (RLM 05). The second successful launch, M17, was painted RLM 04, the color of the bright yellow replica displayed at the Deutsches Museum in Munich.

The only manned launch ever attempted resulted in the death of Bachem-Werke test pilot Lothar Sieber. By most accounts, the craft left the tower and, at about 150 feet, the cockpit cover and headrest came loose. Whether Sieber was injured, knocked unconscious, or struggled to continue the mission, the craft continued a shallow climb to about 5,000 feet before it flew inverted into the ground.

After Germany's surrender, Natters were discovered in various states of readiness. The American troops got to them first, and captured Natters were loaded onto trailers for transportation. Records are vague, but supposedly two Natters were loaded aboard the Royal Navy escort ship HMS Reaper, which carried a number of captured artifacts to New York. Another Natter was supposed to be destined for the UK, but there is no record of it arriving. The whole story now appears unlikely: The two Natters that did arrive in the U.S. could have been transported by aircraft.

These two Natters became known "Unit One" and "Unit Two." Both were displayed at various air shows across America. Pictures of Unit One in August 1945 at the Douglas airfield in Santa Monica, Calif., show it in standard German camouflage on an Army Air Forces trailer outside a hanger. A large placard emblazoned with the slogan "Air Power Is Peace Power" identifies it as "'Viper' BP-20 Rocket-Propelled Interceptor." (BP 20 was the Natter's designation before it was accepted by the RLM).

Unit One still exists. I photographed it in Maryland at the Paul E. Garber storage facility of the Smithsonian Institute's National Air and Space Museum. The fate of Unit Two is uncertain. One story is that it went to Muroc Air Force Base (now Edwards) in California, where it was test-fired and destroyed on landing. However, there are no records to substantiate this theory.

The only other known Natter remains in Germany at the Deutsches Museum in Munich. It represents M17, but it is a reconstruction as this version, for it has a cockpit, a "standard" nose, and an equal number of stripes on its wings (none of which appeared on M17). Another replica, built in 2000, is displayed at the Fantasy of Flight Museum in Polk City, Fla.

- Mat Irvine

Epilogue: Erich Bachem (1906-1960)

What became of the Natter's inventor? After the war, Erich Bachem returned to his prewar hobby of designing and building camping trailers, or caravans, joining the business of a neighbor, Erwin Hymer. Today, in Europe Hymer is synonymous with recreational vehicles (like Winnebago). One of Hymer's popular lines, introduced in 1958, is called Eriba, a name derived, according to Encyclopedia Astronautica, from ERIch BAchem.

- FSM Associate Editor Mark Hembree
Related Issues
Get Our Free Newsletter
Get our twice-monthly newsletter delivered to your inbox
Expand Ribbon
close logo