B-58 question

[Flying Sorcerer]

I assume the B-58's service life (1960-1970) was cut short mainly for economic reasons and doubts about the utility of a fast high-level bomber. How long could it have been kept serviceable if ths USAF wanted to keep it flying?

 

[sferrin]

It could still be flying. Just look at how long F-104s and F-4s have been flying. It wouldn't be cheap though.

 

[Archibald]

Considering the horrendous attrition rate, not many would be left flying by 1980. 26 lost over 116 build, that's 22% of the fleet - right between 1/4 (25%) and 1/5 (20%). All this in only 14 years, 1956-1970. Or even shorter, because 1956 was the year the prototype flew. According to Joe Baugher, entry in service was in March 1960, so that's far shorter.

Service of B-58 Hustler with USAF

 

[sferrin]

Good point. On the other hand, if they'd intended to keep them that long, maybe they'd have made more. They'd be perfect carriers of hypersonic weapons.

 

[Archibald]

Any electronic help to improve the flight characeteristics would be very welcome. surely enough that bird had plenty of room for improvement - B-58B anybody ?

 

[sferrin]

Any electronic help to improve the flight characeteristics would be very welcome. surely enough that bird had plenty of room for improvement - B-58B anybody ?

Had never heard that it was a poor flyer.

 

[TomS]

Any electronic help to improve the flight characeteristics would be very welcome. surely enough that bird had plenty of room for improvement - B-58B anybody ?

Had never heard that it was a poor flyer.

It was definitely a handful.

Speed Freak

In the 1950s, the Mach 2+ B-58 Hustler seemed a safe bet to win the arms race

www.airspacemag.com

The B-58’s complex flight control system was a cause for continual anguish; designers, pilots, and mechanics all struggled with it. Because of the delta wing configuration, the bomber had no horizontal elevators or wing-mounted ailerons. Instead, it had a very complex system of linkages that connected the wing’s elevons (a combination of ailerons and elevators) to the large rudder.

“You would sit there on the end of the runway doing all kinds of checks on the flight controls,” Cotton says. “It was an extremely complex arrangement, centered around the power control linkage assembly. When I preflighted the airplane, I made sure the crew chief had it opened up so I could look up in there to see if there were any hydraulic leaks and that the rods were all connected—the system was a hydro-mechanical-electrical maze.” Most pilots and crew members referred to it as the “three-bicycle wreck” since it looked like the engineers had run three bikes together.

“I think the flight control system led to the loss of a few people and aircraft,” Cotton says. “It took a tremendous amount of understanding. A lot of pilots would tell you that they flew the airplane a long time before they understood what they were doing when they mixed the stick around.”

 

[Flying Sorcerer]

Thank you al. I recall that a large number of accidents occurred during flight testing and that once the -58 became operational it's loss rate was somewhere around 12% during its decade of service life. There was a tactical bomber version (and I think even an air defence variant) proposed but its high cost made that a non-starter. Apparently Curtis LeMay resented it because it cost several times as much as a B-52

 

[apparition13]

If I recall correctly, it had a really narrow angle of attack envelope it which it could be flown. Like 9-17 degrees or some such. It was a bit of a handful. What it really needed was fly by wire.

Good point. On the other hand, if they'd intended to keep them that long, maybe they'd have made more. They'd be perfect carriers of hypersonic weapons.

They had an order for 190+ B-58Bs cancelled at the last minute. The design had canards, so maybe it wouldn't have been as difficult to fly. Presumably any future versions would have addressed handling problems. The B-58 thread also talks about the C (bomber), D (interceptor) and E (tactical bomber) proposals. It had a lot of potential that was never realized.

 

[Richard N]

The son of a GD test pilot told me his father said he didn't like flying in the B-58 and didn't care for the way the engines moved around on the wings in flight.

 

[Pioneer]

Found this interview by Col. George Holt Jr, a B-58 bombardier very interesting and insightful

Regards
Pioneer

 

[Michel Van]

Even if stay longer in service
with chance in doctrine from High altitude supersonic (specialty of B-58)
towards low-level flight toward target (B-1 and B-52)
it would reduce drastic the lifetime of B-58 Airframe, next to that B-58 crashes during low level flight.
i think the B-58 had be pull out service in begin of 1980s, to be replaced by B-1

 

[RetiredAFGuy]

The older guys I served with who had been B-58 maintainers hated that aircraft with a red-hot passion. Very little in the design had any "design for maintainability" forethought given.

Equipment like rate gyros were installed in the wings, behind non-removable panels. Replacing those items required working by feel through an access panel located a full arm's length away from the equipment. Much of the avionics were installed that way, leading to lots of dropped hardware by technicians working by feel, which lead to many man hours expended to recover the hardware and tools.

Not a maintainable aircraft that drove per flight hour maintenance costs higher than the B-52.

 

[TJDougherty01]

For you B-58 fans; the B-58's at Pima Air Museum in Arizona and at the Air Force Museum, Dayton, Ohio:

 

[Byeman]

Good point. On the other hand, if they'd intended to keep them that long, maybe they'd have made more. They'd be perfect carriers of hypersonic weapons.

There is no logic that support that claim.

 

[sferrin]

There is no logic that support that claim.

Oh, of course not.

 

[Byeman]

Oh, of course not.

Where does it state they would be "perfect' at the task?

 

[sferrin]

Where does it state they would be "perfect' at the task?

Okay, fair. But "ideally suited" is close enough.

 

[Byeman]

Okay, fair. But "ideally suited" is close enough.

Can't say that either. it never performed the task so your point was never validated. Was the A-12 "ideally suited" as mothership?

 

[sferrin]

Can't say that either. it never performed the task so your point was never validated. Was the A-12 "ideally suited" as mothership?

Given the B-58 was designed to carry large payloads externally, deploy them from high altitude and supersonic speed, and actually launched several successfully, I'd argue the facts are on my side. With other aircraft would do it better?

King Lofus IV
"Four missiles were initially ordered from Lockheed. The missile project was known under the code name High Virgo and was given project number 199C. In order to save money and speed up the project, Lockheed elected to use proven components from the XQ-5, the X-17, the Polaris and the Sergeant missile programs. The Lockheed-designed ALBM ended up being 30 feet long and had a diameter of 31 inches. The missile was to be guided by an Autonetics inertial system. The rocket engine was a Thiokol XM-20 solid-fuel motor offering a thrust of 50,000 pounds for 39 seconds. There were four guidance fins installed around the exhaust nozzle skirt. The total weight of the missile was about 12,000 pounds."

"On September 22, 1959, a final ALBM
(nicknamed King Lofus IV) launch was conducted,
again out of Eglin AFB, this time in an attempt to
intercept and photograph the newly launched
satellite. The launch, taking place at an altitude
of 37,500' and a speed of Mach 2, went smoothly,
but some 30 seconds later, all communication with
the missile was lost."

WS 138A
"One of the prime considerations in the development
of Weapon System 138Awas that of operational
flexibility. The configuration, as proposed, can be
used either as a two-stage or as a single stage missile
system, depending upon the momentary operational
requirement. The propulsion stages have been sized
in such a manner that the first stage can be used
alone to provide excellent periormance. The nose
cone is interchangeable and can be assembled either
to the second stage or directly to the first stage.
Through use of this modular concept, a range of 861
n. miles can be obtained with one stage from the B-58
with a Mach 2.2 launch at 60,000 feet."

"The missile system, as proposed by Convair, will
meet the periormance requirements specified for the
design launch conditions in the GSR. For this condition
(Mach .73 launch at 40,000 feet) the missile in the
two-stage configuration has a range of 1,068 n. miles,
and for supersonic launch from the B-58 (Mach 2.2
launch at 60,000 feet), it has a range of 1,365 n. miles."

 

[Byeman]

Given the B-58 was designed to carry large payloads externally, deploy them from high altitude and supersonic speed, and actually launched several successfully, I'd argue the facts are on my side. With other aircraft would do it better?

The supersonic capability of the B-58 offers no real advantage as a carrier for hypersonic vehicles over others like the B-52, KC-135, etc.

The B-52 is a proven hypersonic vehicle carrier.

 

[sferrin]

The supersonic capability of the B-58 offers no real advantage as a carrier for hypersonic vehicles over others like the B-52, KC-135, etc.

Of course it does. A missile launched at Mach 2 and 60,000 feet will travel far further/faster than the same missile launched from subsonic speed.

The B-52 is a proven hypersonic vehicle carrier.

So was the B-58.

 

[Byeman]

Of course it does. A missile launched at Mach 2 and 60,000 feet will travel far further/faster than the same missile launched from subsonic speed.

A little, but shock impingement and interactions cause problems.

 

[Scott Kenny]

Had never heard that it was a poor flyer.

Not a poor flyer, but one that required the pilots undivided attention or the plane would slap the pilot upside the head for not paying attention.

Basically all the original Blackbird pilots and RSOs were drawn from Hustler crews, because the Blackbird was similarly intense to fly.

 

[Archibald]

I would say that B-58 big pod and tall undercarriage might have been of interest to drop big rockets and missiles. Been there, done that in my aerospace uchronia: B-58 meets again Bell LR-81, once on its powered pod, later gone to the Agena. I bring them together again.
BUT - to be honest: nothing beat a B-52 and its wing pylon. Even twice as fast, the B-58 (from TOWN HALL documents I'll link) is too small: it was limited to a maximum of 71 000 pounds on its belly pylon.
Compare that to the 130 000 pounds ISINGLASS concept, carried X-15 style.
Of course the XB-70 bury both, and not only because it flies at Mach 3. According to Dennis Jenkins, a XB-70 could have carried up to 200 000 pounds on a belly fairing. But air dropping at Mach 3 might be hair raising...

Of the three, the B-52 wing pylon carrying 130 000 pounds sounds the best bargain.

I have checked air-launch "boost" numbers from varied papers (Burnside Clapp, Sarigul-Klijn and a couple others).

Broadly
- dropping from a B-52: 40 000 ft, 30 degree AoA carves 1100 m/s out of an ascent to orbit 9000 m/s.
- dropping from a B-58: 40 000 ft, 30 degree AoA carves 1600 m/s out of an ascent to orbit 9000 m/s.
- dropping from a B-70: 40 000 ft, 30 degree AoA carves 2000 m/s out of an ascent to orbit 9000 m/s.

So by orbit standard, the supersonic carriers don't make that much of a difference.

 

[mkellytx]

I would say that B-58 big pod and tall undercarriage might have been of interest to drop big rockets and missiles. Been there, done that in my aerospace uchronia: B-58 meets again Bell LR-81, once on its powered pod, later gone to the Agena. I bring them together again.
BUT - to be honest: nothing beat a B-52 and its wing pylon. Even twice as fast, the B-58 (from TOWN HALL documents I'll link) is too small: it was limited to a maximum of 71 000 pounds on its belly pylon.
Compare that to the 130 000 pounds ISINGLASS concept, carried X-15 style.
Of course the XB-70 bury both, and not only because it flies at Mach 3. According to Dennis Jenkins, a XB-70 could have carried up to 200 000 pounds on a belly fairing. But air dropping at Mach 3 might be hair raising...

Of the three, the B-52 wing pylon carrying 130 000 pounds sounds the best bargain.

I have checked air-launch "boost" numbers from varied papers (Burnside Clapp, Sarigul-Klijn and a couple others).

Broadly
- dropping from a B-52: 40 000 ft, 30 degree AoA carves 1100 m/s out of an ascent to orbit 9000 m/s.
- dropping from a B-58: 40 000 ft, 30 degree AoA carves 1600 m/s out of an ascent to orbit 9000 m/s.
- dropping from a B-70: 40 000 ft, 30 degree AoA carves 2000 m/s out of an ascent to orbit 9000 m/s.

So by orbit standard, the supersonic carriers don't make that much of a difference.

@Archibald where do you come up with 130,000 lbs for the BUFF? The stock BUFF is 20-25,000 lbs for the under-wing pylons, Balls 8 was specially modified for X-15 with lots of structural reinforcements, Balls 25 wasn't, and IIRC couldn't do more than 25,000 lbs.

 

[GeorgeA]

@Archibald where do you come up with 130,000 lbs for the BUFF? The stock BUFF is 20-25,000 lbs for the under-wing pylons, Balls 8 was specially modified for X-15 with lots of structural reinforcements, Balls 25 wasn't, and IIRC couldn't do more than 25,000 lbs.

This was the weight mooted for the Model 192 RHEINBERRY vehicle, pre-drop. The LH2 and LOX would have been carried in a tank under the opposite wing, and the vehicle fueled in flight before launch.

To be honest, it’s one of the more squirrelly parts of the Model 192 conops.

 

[mkellytx]

This was the weight mooted for the Model 192 RHEINBERRY vehicle, pre-drop. The LH2 and LOX would have been carried in a tank under the opposite wing, and the vehicle fueled in flight before launch.

To be honest, it’s one of the more squirrelly parts of the Model 192 conops.

Thanks, again 130,000 lbs isn't happening without a big-time structural update.

 

[Archibald]

Thanks, again 130,000 lbs isn't happening without a big-time structural update.

And I readily agree with that statement.

 

[Scott Kenny]

Thanks, again 130,000 lbs isn't happening without a big-time structural update.

It's well within the total load capacity of a BUFF. BUFFs regularly haul ~70klbs of boom and over 300klbs of fuel in total. (That fuel fraction is more appropriate for a freaking rocket than an airplane!)

The question is really how much lift the RHEINBERRY airframe makes at ~400mph. If RHEINBERRY empty is ~25,000lbs, you then add ~70klbs of hydrogen and 35klbs of oxygen to the bird once in the air and it's providing lift... That's 70klbs of LH2 in an absolutely enormous pod under one wing (~490,000 liters capacity!), LOx in a tank in the bomb bay.

Probably have to run both wings more or less empty of jet fuel to have the overall weight acceptable, but then you can pump 100klbs of jet fuel out of the fuselage tanks and into the wing where the hydrogen pod is to keep the balance within limits. I'm pretty sure a B52 won't particularly notice ~25klbs out of balance on the wing pylon. Rebalancing after the drop is likely to be scary, though. I'm sure a B52 will not be happy about ~100klbs out of balance on the wing.

 

[BlackBat242]

We aren't quibbling about total payload capacity... the problem is with hanging that much weight OFF ONE PLACE UNDER THE WING!

The wing structure cannot carry that much weight without a complete redesign for new-build wings - serious (and heavy) reinforcement would be required to even go past 25,000 lb hanging from the pylon.

 

[Yellow Palace]

So by orbit standard, the supersonic carriers don't make that much of a difference.

By way of comparison, assuming an effective exhaust velocity of 4.5 km/s, you could get the following weights into orbit:

• B-52 - 22,465 lb / 11,710 lb
• B-58 - 13,710 lb / 7,980 lb
• B-70 - 42,215 lb / 26,435 lb

The first figure is gross, second figure is net of stage weight assumed at 10% of total fuel weight, all rounded down to the next lowest 5 lb. Figures for a 3 km/s effective exhaust velocity and 6% stage weight are... underwhelming. But generally, the lower the rocket stage performance, the bigger the advantage of a higher performance airbreather.

I think it's fair to say that any heavy space launch derivative of a bomber would require significant structural alterations. If it stays within the overall weight limits of the aircraft, those should be limited to more-or-less local redesign.

 

[Mark Nankivil]

By way of comparison, assuming an effective exhaust velocity of 4.5 km/s, you could get the following weights into orbit:

• B-52 - 22,465 lb / 11,710 lb
• B-58 - 13,710 lb / 7,980 lb
• B-70 - 42,215 lb / 26,435 lb

The first figure is gross, second figure is net of stage weight assumed at 10% of total fuel weight, all rounded down to the next lowest 5 lb. Figures for a 3 km/s effective exhaust velocity and 6% stage weight are... underwhelming. But generally, the lower the rocket stage performance, the bigger the advantage of a higher performance airbreather.

I think it's fair to say that any heavy space launch derivative of a bomber would require significant structural alterations. If it stays within the overall weight limits of the aircraft, those should be limited to more-or-less local redesign.

Snce you're crunching numbers, how does Stratolaunch compare?

Enjoty the Day! Mark

 

[GeorgeA]

Thanks, again 130,000 lbs isn't happening without a big-time structural update.

Noted at the time. From the Isinglass FOIA file on NRO.gov:

 

[Archibald]

Snce you're crunching numbers, how does Stratolaunch compare?

Enjoty the Day! Mark

A 250 mt S-IVB "doubled" with optimistic isp and mass fraction could lift 18 mt to orbit (I did the maths a while back).

 

[mkellytx]

It's well within the total load capacity of a BUFF. BUFFs regularly haul ~70klbs of boom and over 300klbs of fuel in total. (That fuel fraction is more appropriate for a freaking rocket than an airplane!)

The question is really how much lift the RHEINBERRY airframe makes at ~400mph. If RHEINBERRY empty is ~25,000lbs, you then add ~70klbs of hydrogen and 35klbs of oxygen to the bird once in the air and it's providing lift... That's 70klbs of LH2 in an absolutely enormous pod under one wing (~490,000 liters capacity!), LOx in a tank in the bomb bay.

Probably have to run both wings more or less empty of jet fuel to have the overall weight acceptable, but then you can pump 100klbs of jet fuel out of the fuselage tanks and into the wing where the hydrogen pod is to keep the balance within limits. I'm pretty sure a B52 won't particularly notice ~25klbs out of balance on the wing pylon. Rebalancing after the drop is likely to be scary, though. I'm sure a B52 will not be happy about ~100klbs out of balance on the wing.

The jet cannot takeoff legally with full tanks, much less with a max payload and full tanks. The empty weight is about 185,000 lbs, max gas is 312,000 lbs and max gross is 488,000 lbs. You'll be almost 10,000 lbs over with full tanks. The most I ever saw was 260-280,000 lbs when we flew from ED to EG to shoot a MALD. We had two HSAB's, a MALD and was just about grossed out. We took off at 0600 from 04R (15,000 ft) and it was the longest, slowest takeoff roll I ever experienced. The 70 knot time was long. We had an hour at the range and then took 60,000 lbs of gas to get home.

I don't even want to think about the weight and balance problem, it wouldn't be pretty.

 

[Scott Kenny]

The jet cannot takeoff legally with full tanks, much less with a max payload and full tanks. The empty weight is about 185,000 lbs, max gas is 312,000 lbs and max gross is 488,000 lbs. You'll be almost 10,000 lbs over with full tanks. The most I ever saw was 260-280,000 lbs when we flew from ED to EG to shoot a MALD. We had two HSAB's, a MALD and was just about grossed out. We took off at 0600 from 04R (15,000 ft) and it was the longest, slowest takeoff roll I ever experienced. The 70 knot time was long. We had an hour at the range and then took 60,000 lbs of gas to get home.

I don't even want to think about the weight and balance problem, it wouldn't be pretty.

Right, the way I see it, the plane would take off with about 150k in jet fuel and ~105k in rocket fuel and oxidizer, and use 100klbs of jet fuel as ballast. You can stick some 100klbs of fuel into one wing, right?

Ironically, the reinforcement would need to be on the hydrogen side most of all, since you're packing ~70klbs of hydrogen and
oops, completely messed up on the chemical equation balances!

*facepalm*

Oxygen is 16x more massive than hydrogen per mole, so 2lbs of LH2+16lbs of LOx for stoichiometric combustion. That greatly helps the weights/volumes. 100klbs of fuel and oxidizer divided by 18 is 5,556, 16 x 5,556 = ~88,900lbs LOX and 11,100lbs of LH2 out under the other pylon. ~70,500 liter tank for the LH2 plus insulation volume. 35,500L tank for the LOx.

So the LH2 tank wouldn't be any heavier than 12x ALCM on the pylon. I'd hate flying with ~90klbs of LOx in the belly.

Sitting on the ramp, RHEINBERRY would weigh ~25-35klbs under the wing. The question is how much lift would it generate at 400mph as you fuel the beast? Obviously, at whatever design cruise speed was it'd lift at least 75klbs. But if it generates more or less 25klbs of lift at 400mph the pylon only needs to be rated for ~100k. Which is a hell of a lot, but better than having 135klbs sitting there static.

 

[mkellytx]

Right, the way I see it, the plane would take off with about 150k in jet fuel and ~105k in rocket fuel and oxidizer, and use 100klbs of jet fuel as ballast. You can stick some 100klbs of fuel into one wing, right?

Ironically, the reinforcement would need to be on the hydrogen side most of all, since you're packing ~70klbs of hydrogen and
oops, completely messed up on the chemical equation balances!

*facepalm*

Oxygen is 16x more massive than hydrogen per mole, so 2lbs of LH2+16lbs of LOx for stoichiometric combustion. That greatly helps the weights/volumes. 100klbs of fuel and oxidizer divided by 18 is 5,556, 16 x 5,556 = ~88,900lbs LOX and 11,100lbs of LH2 out under the other pylon. ~70,500 liter tank for the LH2 plus insulation volume. 35,500L tank for the LOx.

So the LH2 tank wouldn't be any heavier than 12x ALCM on the pylon. I'd hate flying with ~90klbs of LOx in the belly.

Sitting on the ramp, RHEINBERRY would weigh ~25-35klbs under the wing. The question is how much lift would it generate at 400mph as you fuel the beast? Obviously, at whatever design cruise speed was it'd lift at least 75klbs. But if it generates more or less 25klbs of lift at 400mph the pylon only needs to be rated for ~100k. Which is a hell of a lot, but better than having 135klbs sitting there static.

I'd have to look in the -1 and I don't mine handy ATM. That amount of imbalance wouldn't be good, heck it's more likely than not prohibited, but as I said I don't have my -1 handy.

Edit:

Forgot to add fuel usually feeds from the wings (again no -1 so the weasel word), so can't pump everything, Also, when we planned X-51 the pilots brought up that we'd damage the airframe if we tried to land with less than 20,000 lbs on the jet, it was a major constraint for that mission plan.

Edit #2:

Also, forgot there was the first synthetic fuel mission that I conducted with an Undersecretary of the Air Force onboard that we blew a hydraulic line and couldn't extend an outrigger, so we purposely burned down an imbalance to keep that wing tip off the runway (bad form to drag a pod on the tarmac) and it was only 10-20,000 lbs, maybe 30,000 lbs max because stayed airborne less than an hour after the failure. So, it doesn't take a lot to affect the roll axis.