LowObservableOK Spud, document time again.
Please cite a formal definition of “low observable”, “very low observable” and “extremely low observable” from a credible source.
Since the dog probably ate your computer again, I’ll help: There are no such definitions. ELO/VLO has some uses, but the details get classified pretty fast. The result is that the Wiki entry doesn’t tell people a whole lot.
Have you looked up “sciolist” on Wiki lately?
LowObservableThe Dec 2011 SAR is now out. Watch for cost numbers to break loose pretty soon.
IOT&E does not complete until April 2019 (“threshold” is October).
Op cost per hour is 42 per cent more than the F-16C/D, in USAF service in 2011.
The death spiral beckons.
On acquisition costs, the SAR shows that at full 80/year rate – in the FY2021 buy year, delivered in 2023 – if all goes perfectly (sure), the F-35A will cost $76 million (flyaway) in BY2012 dollars. This is 13 per cent more than a Super Hornet today, at 28 rather than 80 aircraft a year, and including two-seaters. It also assumes full Navy, Marine and partner buys.
And, of course, the SH price is real and contracted, and not an 11-year projection for a program that hasn’t been stable for a year yet.
In other news, Spudman, who tells us he can’t find any documents to support the flimsy body-lift case, asserted body lift as the vital missing element in F-35 performance over at the kiddy playspace on March 27.
http://www.f-16.net/f-16_forum_viewtopic-t-18921-sid-3eb3330dc8a84b6074819689d006eb6d.html
LowObservablePity that it doesn’t work, and if it does, will have resolution about half that of your cell-phone camera.
LowObservableHaavarla – Interesting. Had not thought of that aspect of the centroplane design.
Now, if there are some aerodynamicists around, they can refute the following:
Any object will produce some lift if it is pushed through the air at a nose-up angle. It’s how missiles turn. The forward movement creates air resistance, and that resistance can be resolved into two vectors – upwards (lift) and backwards (drag).
However, cambered wings produce lots of lift and little drag, while the opposite is true for tubes and bricks.
Classical aero performance estimation simply ignores body lift at level flight and low alpha. We don’t measure wing area to the wing-body junction but project the LE and TE to the centerline and measure that.
Now, as the body gets broader and flatter it can be made to be more wing-like and may actually become a wing. There is a continuum from pure cigar-and-Popsicle-stick designs through mildly blended things like F-16s, big-Lerx designs like F-18s and the Russian fighters all the way to BWBs and pure wings.
However, what all the F-16-to-Russian blended designs have in common is a flaring-out of the body in cross-section, so that the section gets thinner (more wing-like), and a leading edge configuration that trips a vortex and gives you some nonturbulent (or at least stable vortical) flow over the top.
I don’t see the F-35 shape doing that, with the relatively narrow forward-raked inlet lip. Indeed, if there was supposed to be any body lift, they sure as heck wouldn’t have put that THING on the upper left side of the F-35A.
Back to the classical estimation of wing area: On how many non-blended aircraft does the body (the brick) account for as large a proportion of the total span and gross area (measured to centerline) as it does on the A and B?
Conclusion: The effective wing loading of the A/B – that is, weight divided by the net wing area, or the area that produces lift with any efficiency – is off the scale.
Have at this theory for all you’re worth… except Nopia, who seems to be back from ‘is trip abroad, as we used to say in ‘ackney, but is still on my ignore list.
LowObservable“That is the definition of an SDD program.”
Odd, I remember somebody – General Davis, or some name like that – saying it was all about validation.
“I don’t have time at work and my home laptop is on the fritz until I can get a new one next month to do detailed research.”
In that case, I’ll save you some time: The body-lift myth is a fan invention and nothing else.
LowObservableDesperate measures… Sure, you can throw a God’s Eye View of what the DAS is seeing on the panel. But how do you display range when you don’t always know what it is (or with different degrees of confidence)? How do you show elevation?
Spud, Spud, Spud – it’s so easy to declare the problem solved. Hey, where are the sources for the body-lift stuff you were selling us a few pages back? You went all quiet on that (probably because the source is a gamer on a fan page).
Sintra – “As of today that particular criteria (360º IR night vision outside of the cockpit) cannot be met by any other aircraft”… DINGDINGDING we have a WINNAH.
Exactly. The Canucks said “zero light”. Anyone else selling fighters will say “excuse me but when are you going to do air combat in zero light – in a cave? at night under dense overcast, over water or unpopulated land?” The requirement was obviously written to disqualify anything except JSF.
LowObservableMildave
LOL all the naysayers was wrong wen they sed it couldnt fly at nite becuse they would lose it in the dark thatll show them
//Australian troll mode off
LowObservableLack of cash, Spud?
Considering the annual spend rates on upgrading 140 operational F-22s, I’d be interested in seeing what a fully funded modernization program would look like.
I suspect that the AIM-120D and AIM-9X timelines have more to do with delays and overruns in earlier upgrade efforts. By the way, LM gets paid for this on an ID/IQ basis rather than fixed-price + incentive. Wonder how that will play out on F-35?
LowObservableSpud – You are oversimplifying, grievously.
First of all, let’s be honest and say “if”, not “when” the F-35 gets to 200 a year. Not in this decade, for certain.
Second, what’s loosely referred to as “learning curve” has at least three elements:
1 – Everyone on the line in the supply chain gets better at doing their jobs with repetition. However, this is not linear and eventually flattens out, so that more jets = more people.
2 – As the product and processes mature, fewer engineers are needed to sort out production glitches, and to incorporate changes coming out of testing.
3 – Fixed program overhead (for example, production facilities built for 200 aircraft a year) reduces per unit as the numbers go up.
Third – What follows from the above is that higher rates are good, but the relationship is not direct. What’s important is that the production system and supply chain are tailored to whatever the rate may be. Note that Boeing’s been able to throttle C-17 down to ten jets per year without the unit cost going through the ceiling. And Airbus and Boeing can both build big jets at low rates, and sell them at prices that are competitive with their smaller long-range aircraft.
Fourth – Airplanes are made out of parts, so you have to look at the part supply chains, not just final assembly. The first JAS 39E/F will have F414 engine S/N 1000+ and the T/R modules in the radar will come from the foundry that supplies the AESAs on USCG HC-130s and CBP King Airs today.
Also: The Noggies inflated the NG program cost by assuming very high through-life upgrade costs divided by a small global fleet. Meanwhile, they accepted LMT projections of their costs and divided by 3,000.
As for this:
There are a lot of fixed, yearly costs involved in fighter programs that add a lot to their costs. These include (but are not limited to) rent & upkeep on factory space, ongoing development of maintenance procedures as problems appear, development of upgrades, integration of new weapons & equipment, development of pilot & maintainer training programs, Component Improvement Programs, etc, etc.
Your first obvious error is to describe factory space as a fixed cost, when clearly it varies with the number of jets you’re building. Also, these costs are not the same for all programs or all contractors. I would go compare the cost of the entire JAS 39C/D effort with a typical year of modest progress on F-22 upgrades. And (to repeat) engine-related ongoing costs on the NG will be shared with the SH fleet.
PS – Put it this way: Last year Airbus delivered 87 A330s and 26 A380s. Do you think that the A380 price would be close to that of the A330 if the numbers were the other way around?
LowObservableAussienscale – If you don’t know “center of gravity” and “lift to drag ratio” you require more education than I have time to give you. And as for the difference between the F-22 and F-35: The specs didn’t allow the same kind of shaping to be used.
Spud – I suspect that the higher cost of the C has to do more with complexity (add hook, wing fold, ailerons), lower volume and reduced commonality than with just the price of a ton or so of material.
LowObservableSpud – Isn’t instability having the CG aft of the center of pressure? Can you explain how a long forebody equates to an unstable configuration?
And everyone forgets about body lift… but how does the body produce lift, except at high alphas and very low L/D? Considered as a lifting surface, it has very little continuously cambered upper area, nor does it have a sharp, swept leading edge (like the Russians or the F-22).
Is there a primary source out there, even an interview with a program engineer, which explains the use of body lift in the F-35? Because all I find is fans using it as an excuse for the jet’s lousy wing loading numbers.
LowObservableObligatory – And of course we have the same trend in operating cost projections, starting with the day when the CPFH was to be lower than an F-16C.
Spud – $65m flyaway should inflate to around $75m in 2017, so the estimated price has a long way to come down to meet that projection.
And that $65 m estimate, as a man of your diligent researching skills might have find out had you looked, has been described as “disingenuous”. By APA? By Sweetman? Er, no, by the JSFPO:
http://www.defensenews.com/article/20110912/DEFSECT01/109120306/What-s-Price-Tag-Production-F-35-
LowObservableThe engine has to be a huge factor in that result. Having Volvo try to replicate the F414 program for a small production run, versus piggy-backing on USN’s investment, would be hard to justify.
LowObservableOh, sorry, “upper 40s”, according to what some schmow posted on f16.net…
http://www.f-16.net/index.php?name=PNphpBB2&file=viewtopic&p=155869
$45m 2001 = $58 m today with normal inflation.
LowObservableSaith Spud: “The answer to both is that customers trust in the ability of the US to produce fighters to match the paper spec.”
Like the dozens of IOC-spec, $40 million, lower-cost-per-hr-than-an-F-16 F-35As that are rolling off the production line every month as we speak?
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