The Air Force’s high-speed, deep penetrating, high-altitude XB-70 Valkyrie bomber was once expected to replace the time-honored B-52.
However, due to a complex set of factors, it wound up dissolving into the realm of history on display at the National Museum of the United States Air Force.
XB-70: Cold War Origins
The bomber, which first took to the skies as a developmental prototype as far back as 1964, was designed in the 1950s as a Cold War answer to Soviet threats.
Expectations for the aircraft were that it would reach at the time unprecedented speeds for a bomber and cruise at Mach 3 at extremely high altitudes of 70,000 feet.
The idea was to use altitude and speed to elude enemy air defenses and hold enemy territories at risk of nuclear air attack.
Multiple reports say the XB-70 performed well as a prototype but ultimately never came to exist as the Pentagon determined it would not out-perform the B-52 in terms of range and was more expensive.
Also, the advent of advanced Soviet-built air defenses made the XB-70 less survivable in potential great power engagements.
In response to highly-capable Soviet air defenses, the XB-70 was then developed to a certain extent as a lower-altitude bombing option, something which did not fully evolve or prove very effective tactically, according to various online writeups on the XB-70.
However, while budget considerations always figure prominently and of course there is no question about the long-standing value of the B-52 both during the Cold War and today, yet there also does appear to be an interesting argument to suggest that indeed the Air Force should have been allowed to buy the XB-70.
A super high-speed, high-altitude supersonic bomber would arguably still have relevance today for a number of key reasons.
First of all, a non-stealthy B-52 certainly cannot operate in a contested environment and a faster and higher altitude nuclear bomber could multiply the threat equation for an enemy.
Even if an XB-70 were somewhat vulnerable to air defenses, it might prove useful in support of stealth bombers or other assets as part of a campaign, and its speed and altitude would still likely make it difficult to target.
By extension, even if it were vulnerable to some air defenses, it would clearly be much more survivable than a B-52 yet still be able to project airpower and carry a sizable payload.
Perhaps the previous existence of the XB-70 could inspire thinking about a possible new aircraft in the future. Being from the 1950s-era in terms of concept, it is not likely the XB-70 would prove extremely relevant today, however upgrades to the 1960s-era B-52 will enable the bomber to fly for several more decades. A faster, heavily armed high-altitude bomber concept is something which the Air Force might be well-served to consider in the future as a nuclear air attack option somewhere in between a stealthy B-2 or large, vulnerable bomb-truck like B-52.
Kris Osborn is the Military Affairs Editor of 19FortyFive and President of Warrior Maven – Center for Military Modernization. Osborn previously served at the Pentagon as a Highly Qualified Expert with the Office of the Assistant Secretary of the Army—Acquisition, Logistics & Technology. Osborn has also worked as an anchor and on-air military specialist at national TV networks. He has appeared as a guest military expert on Fox News, MSNBC, The Military Channel, and The History Channel. He also has a Masters Degree in Comparative Literature from Columbia University.