Talk:Northrop YB-49/Archive 1

Archive 1

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I'd get the impression that this aircraft was quite an inspiration for the B-2_Spirit , just by looking at the photo even. I also vaguely recall that Northrop had built an earlier flying wing design that even already had some stealthy properties by accident. Would the story be relating to this aircraft? Kim Bruning 13:50, 31 Mar 2004 (UTC)

Northrop YB-49

A 2001 paper shows that the YB-49 was cancelled not because of Jack Northrop's refusal to merge Northrop with Convair, but because of unceremonious postponements in the B-49 project (45% percent greater production potential, stability problems, and medium area of Northrop's manufacturing plants).

Both B-49s have been known as the YB-49, but the 1st aircraft is believed to have used an XB-49 designation, while the 2nd was designated YB-49, because of its closeness to a production version.

It was cancelled because with the state of the art at the time it could not be made to fly right. Conventional bombing accuracy was poor and it could not carry the contemporary nuclear weapons. - Emt147 ^Burninate! 01:09, 5 May 2006 (UTC)

New comment: Yes the flying wings initially had yaw stability problems, but installation of a yaw damper coupled to the autopilot solved it. Initial Convair B-36 production bombers also could not carry the atomic bomb, they had to undergo expensive bomb bay mods. Similar mods would have allowed the B-49 to carry two atomic bombs.

The flying wings did not have any greater problems than their competition (the B-36 and B-47), but the Air Force was reluctant to try and fix a radical new design due to the perceived higher risk, and instead opted to fix the conventional designs. TBrummer (talk) 18:40, 12 August 2009 (UTC)—08:22, 6 August 2009 (UTC)

Reasons for the Cancellation

I agree that part of the reason for the cancellation of the YB-49 was Jack Northrop's refusal to become part of former General Reuben Fleet's monopoly of aircraft subsideries. Another reason for the cancellation most likely came from uncertainty concerning the stability of the YB-49. After the crash of Capt. Edwards' prototype one YB-49 and the destruction of the second prototype during a taxi run, the flying wings looked to the Air Force to be unstable and unsafe. This definately contributed to the cancellation. I also beleive that the Air Force was reluctant to spend more of their money on a design that was going out on a limb. With a standing partiality towards Consolidated Vultee, the bad reports given to the Air Force were just enough for them to decide to give up the futuristic design, which in all honesty knocked back the development of advanced aircraft thirty years, when the blended wing body design was rediscovered in the B-2. Hopefully the government will be more open minded in the future, but that is going out on a limb itself.

Cancellation Reasons Cited by Author Daniel Ford in His Publication of Glen Edwards' Diary

First, some background information: A YB-49 Flying Wing crashed in June 1948, killing Captain Glen Edwards and four other crewmen. Major Russell Schleeh eventually took over as chief military test pilot, for the YB-49, from Major Robert Cardenas. During Russ Schleeh's high-speed taxi test of a YB-49 in 1950, its nose gear collapsed and the craft broke apart and burst into flames. His own back broken, Schleeh yelled to the fire chief to "let the bloody thing burn!"

From the book, Glen Edwards: the diary of a bomber pilot, by Daniel Ford and Glen Edwards (New York: Smithsonian Books, 1998, ISBN 1-56098-571-2. 195 pages.) Quotations from pages 176-178:

So it was a hollow triumph when, in January 1949, Bob Cardenas took the surviving YB-49 on a high-speed exhibition run to Washington, D.C., setting a new cross-country record for multiengine aircraft.

The YB-49 was next used for a secret project that may have involved its stealth capabilities, which Max Stanley had noted while flying over a radar station near San Francisco. (The radar operators couldn’t see the aircraft until they stepped outside and looked with their unaided eyes.) Here was a role for the Flying Wing. Unfortunately, the Air Force wasn’t yet interested in aircraft that were difficult to see on radar. The B-36 carried a bigger load, twice as far, and so high that enemy fighters couldn’t touch it. In comparison, the Flying Wing was a medium bomber, no match for the Boeing B-47 Stratojet that was at about the same stage of development. When Cardenas flew the YB-49 to Washington to impress the press and the politicians, he averaged an impressive 511 mph … but Russ Schleeh followed him in an XB-47, and Schleeh made the trip at 603 mph.

Nor could the gap ever be closed. "Northrop had insisted that the crew, fuel, and everything else had to go into the Wing," explained Theodore von Karman, who as consultant to Northrop had helped design the Flying Wings. The result, von Karman explained, was a thick, blunt airfoil without any camber, which at high speeds “began to shake and lose stability.” Boeing’s new turbojet could fly faster, higher, and nearly as far—and it could carry a Fat Man plutonium bomb. For those reasons, the B-47 had been ordered into production in September 1948, before the YB-49 failed its first bombing trials. (1)

Equipped with a modified Honeywell autopilot called "Little Herbert," the Wing went through a second round of tests with Russ Schleeh at the controls. According to Northrop executives and pilots, these were a complete success. Schleeh remembered otherwise: "You could drop a bomb with it," he said in a 1983 interview, "but it wasn’t nearly as good as the other aircraft of the day." Testing continued until the aircraft was destroyed in a high-speed taxi test in 1950, in which Schleeh broke his back.

By this time, most of the Flying Wing airframes had been cut up by acetylene torches and melted into aluminum ingots. This act, more than all others, was cited by Jack Northrop as proof of Stuart Symington’s vendetta against his design. But what else could the Air Force have done with the airframes, which by July 1949 represented a sunk cost of $66 million. Should it have paid Northrop additional millions to complete the planes, just so they could be flown somewhere else and then scrapped? (2)

One airframe was spared to test the reconnaissance configuration, which had four engines buried in the airfoil, plus two suspended below. Jack Northrop hated the pods, but they freed up space for additional fuel. (Unfortunately, the change actually reduced the plane’s range over that of the bomber version, thanks to increased drag and a requirement that the fuel cells be made leakproof.) The YRB-49A, as it was called, made a dozen flights in 1950 with company pilots. In April 1951, Colonel Boyd flew it to its final resting place at the airport in Ontario, California.

Broken by the failure of his beloved Flying Wing, Jack Northrop turned the company’s management over to the same Oliver Echols who, as commander of the Air Materiel Command in 1944, had grumbled about the teething problems of the XB-35. Northrop retired in 1952, an old man at the age of fifty-seven. After forty years as an airframe designer and builder—one of the first to use the skin of an aircraft as a structural element; one of the first to fasten aluminum by means of flush rivets and magnesium by means of welded seams; and one of the first to build a true Flying Wing—this self-taught genius made no further contribution to American aviation.

In November 1953, after a Republican administration had replaced the Democrats in Washington, the YRB-49A was scrapped at Ontario Airport. This is a fact hard to reconcile with Jack Northrop’s charge that the Wings were destroyed as an act of vengeance by Harry Truman’s secretary of the Air Force: what did the Republicans care about Symington’s revenge? In any case, far from being destroyed by vendetta, the company actually prospered under Air Force contracts, from its F-89 Scorpion fighter (1,000 copies sold) to its B-2 stealth bomber, the most expensive aircraft ever built.

Because the B-2 is an all-wing, built by Northrop, with a span identical to that of the earlier Flying Wing bombers, it is often cited as a vindication of Jack Northrop’s design. In truth, it more nearly resembles an all-wing fighter-bomber built by Reimar and Walter Horten in Germany toward the end of World War II, with camber, a thin airfoil, and dorsal humps to accommodate the engines and crew. The B-2 even vents its exhaust onto the top surface of the airfoil, as the Hortens did with their turbojets.

The argument is unresolvable. Jack Northrop’s charge that he was wronged by the generals and the politicians is like most conspiracy theories: it thrives precisely because the evidence doesn’t exist to prove the case either way. But it seems to me that the Flying Wing failed for a variety of very good reasons:

First, it was too slow to compete with the new generation of turbojet medium bombers. That sluggishness was the inevitable result of Jack Northrop’s design principles, as Theodore von Karman pointed out.

Second, it lacked the range to compete with Convair’s big Peacemaker or the next-generation B-52 Stratofortress from the Boeing company. (3) Midair refueling would make extreme range less crucial in the 1950s, but no reliable refueling system existed in 1948.

Third, Jack Northrop built his Flying Wing a generation before the technology existed to control it. The B-2, like most modern warplanes and even some airliners, is deliberately unstable: it’s not flown by its human pilots, but by an array of onboard computers. This technology did not become feasible until the 1980s.

In my judgment, Jack Northrop’s Flying Wing bomber was a design failure. The YB-49 airframe had been crafted for a vanished era of piston engines, and it required technology from the future before it could have done the work required of it. Nobody killed the Wing; it died a timely death.

I’m tempted to add that five men died as a result of this design failure, but I suspect that the principal author of this book wouldn’t have agreed. Glen Edwards lived with death, from 1941 to 1948. Many of his best friends had died—more of them in accidents than in combat. Danger was part of what a pilot did, and especially what a military test pilot did. Edwards loved to fly, and his country gave him planes to fly. In the end, the bargain killed him, but I don’t think he would have complained. At most he might have said: Blast the luck.

---

(1): The Air Force order of B-47s in September 1948 followed the shocking crash of the Glen Edwards-Daniel Forbes YB-49 that killed five crewmen just three months earlier in June 1948. That terrible tragedy should not be ruled out as significantly impacting the Air Force decision.

(2): Daniel Ford’s arguments ignore that Northrop had at least six spare YB-49 airframes in various stages of completion, some of them highly completed. Even one of those revolutionary aircraft could have been finished and preserved, and perhaps even sold as a museum piece to recoup some government cost. At the minimum, Northrop Aviation itself should have been given the opportunity to acquire and secure the craft, rather than being forced to destroy all of them for scrap.

(3): It is not valid to compare the developmental stages of the YB-49 with the B-52, because the latter was a later generation aircraft with its first flight four years after that of the YB-49. The YB-49 should be compared with the same-generation B-36 and B-47. The B-36 range was nearly 6,800 miles, with a 10,000-lb bomb load, compared to the YB-49 range of 3,155 miles with a 16,000-lb bomb load. However, the B-36 cruising speed was only 230 mph, compared to 419 mph for the YB-49. —Preceding unsigned comment added by Leonard Zane (talk • contribs) 18:05, 17 January 2010 (UTC)

"It is not valid to compare the developmental stages of the YB-49 with the B-52"

I would suggest that it's also arguably not valid to compare the performance figures, especially in terms of range, of the YB49 with the B36. The B36's longer range was largely due to its primary powerplants being piston engines which (in 1940s technology) gave much better "gas mileage" than the primitive J35 turbojets used in the YB49. A fairer comparison (to compare the airframe qualities) would be between the B36 and the XB35 as both used similar P&W R-4360 engines. In this comparison we see the XB36 had marginally greater range (on a third of the fuel) and slightly higher cruise speed, but with 28% lower payload. Some comment that the XB35 couldn't reach the same cruising altitude, but this wasn't an airframe issue - the 15,000ft ceiling was a limitation of the crude piston-engine APU (actually an automotive engine) that had to be used because the AAF-provided engines were never fitted with the alternator/generator sets that had been promised. It would have been really interesting to see the XB35 configuration tried with four 4,000shp turboprops which would have had better specific fuel consumption than the piston engines and to a much higher altitude, but those developments weren't available at the right time. 213.205.192.120 (talk) 10:41, 20 April 2023 (UTC)

Some consideration to mentioning early stealth features

I believe that, in some other documents regarding this aircraft, there is mention that the flying wing was more difficult to pick up on RADAR. If true, this would be a good addition to add to this article. 147.145.40.44 22:04, 16 January 2007 (UTC)

Agreed. I've seen references somewhere to the YB-49 having the same wingspan as the B-2 Spirit. Jack Northrup has been known as the man who proved the Air Force wrong about his flying wing design. It only took a few decades for the key missing piece -- fly by wire -- to arrive on the scene. 74.131.191.192 23:24, 12 August 2007 (UTC)

Wrong, the B-49 did not need fly by wire for stable handling, a yaw damper had been installed in 1948 which gave it stable handling. The problem was the Air Force at the time did not trust "artificial stability", they wanted "aerodynamic stability". Of course now ALL new warplanes since the F-16 have "artificial stability", I suppose you can thank Jack Northrop and the B-49 for starting that trend, the problem was Jack was so brilliant it took 20 years for everyone else to catch up and understand and trust what he was doing was right!!

The AF could have deployed a stealth bomber in 1950 but they simply were not smart enough, from Stuart Symington on down, to understand the technology or it's benefits. TBrummer (talk) 18:53, 12 August 2009 (UTC)

Ferry Range?

Is it really necessary to ferry this thing 53,000 miles? Methinks the figures might be a little off.--Asams10 03:49, 16 August 2007 (UTC)

OFFICIAL NORTHROP SPECIFICATIONS

There seems to be a great deal of contradictory data and misinformation presented on the Internet regarding the Northrop XB-35/YB-35 and YB-49 Flying Wings. Regarding specifications and performance, the facts are available from official Northrop published data. Northrop did so in their wonderful 290-page book, published in 1976. The reference is shown below, along with some YB-49 Specifications data from page 112; so the Wikipedia article on this should be edited accordingly.

Anderson, Fred. NORTHROP – An Aeronautical History (Los Angeles: Northrop Corporation, 1976. Library of Congress Catalog Card Number 76-22294. P. 112).

SPECIFICATIONS FOR THE YB-49: WING SPAN 172 FT.; OVERALL LENGTH 53 FT., 1 IN.; OVERALL HEIGHT 15 FT., 2 IN.; WING AREA 4,000 SQ. FT.; TAKEOFF WEIGHT 196,193 LB; SPEED-MAXIMUM 493 MPH; SPEED-CRUISING 419 MPH; RANGE 3,155 MILES; SERVICE CEILING 40,700 FT.; BOMB LOAD 16,000 LB. —Preceding unsigned comment added by Leonard Zane (talk • contribs) 17:20, 17 January 2010 (UTC)

In the Media

There should be some way to make the heading look normal instead of reflecting the URL. Was it really necessary to remove a 1-line media blurb that accompanied this link? Over-linking rears its head. —Preceding unsigned comment added by 4.230.117.201 (talk) 17:50, 2 November 2010 (UTC)

Rear cockpit?

In pictures, and at 6:08 in this video (https://www.youtube.com/watch?v=L_MaG5G46pA), there is a rear cockpit. Who sat in this seat and why was the decision made to place a crew member(s) there? 22:15, 27 November 2019 (UTC) — Preceding unsigned comment added by Axeman (talk • contribs)