FA/18 crash

[Pilotasso]

Mines Top Hatters. But my absolute favourite are the Jolly Rogers, I have an F-14 kit around to make from that squad.

[Vekkinho]

Sorry for straying OT but I didn't know you're into scales as well, I must admit I got rusty lately (lack of free time) but there's VFA-31 F/A-18E CAG bird and VFC 12 Fighting Omars F/A-18C in 1:72 on my shelf waiting assembly.

[Pilotasso]

Here:

 

http://forums.eagle.ru/showthread.php?t=57423&highlight=scale

 

Still didnt go around to finish all of them.

[Phantom88]

I'm sorry Frostiken but these enthusiasts are right about nozzles. Pictured here is RAAF F/A-18C and cold GE F404-400 engines look like this:

 

 

Nozzles are closed not open!

 

You do have a point,Here's iphone pic of F model Rhino I took at Oshkosh last yr.Obviously engines off

 

[Vekkinho]

Conclusions

 

We'll have to see what will be revealed about the crash in the days and months to come.

 

From a preliminary look at some of the available sources, I would theorize that:

• The aircraft took off from NAS Oceana, runway 5R
  
• After becoming airborne, the aircraft continued on heading 050 (+/- a few degress)
  
• At an unknown time (but within a 0 to 55 seconds window after takeoff), the left engine failed
  
• The crew started to drop fuel in response to the engine failure
  
• The crew ejected only moments before the aircraft crashed into a highly populated area
  
• The aircraft had not altered its heading one bit throughout the whole flight
  
• IMHO, that leaves two possible reasons for crashing into a populated area:
  
  • Complete failure of flight controls
    
  • The crew underestimated the emergency situation or did not react in time to stear clear of a populated area
    

   

 

Or starboard engine got stuck in AB?

 

This is VERY strange, no hooks no turns initiated by any of the two to crash into unpopulated area.

 

That's why green lines sound very plausible.

[aaron886]

It never seizes to amaze me how many opinions are given and wild theories stated on single eye witness reports and some such. As others have said before, we won't know anything for sure unless an (official) preliminary report comes out.

 

You say that, then provide 800 words worth of fabricated explanations? Your "conclusions" are disjointed at best.

 

Quoted Dump rate FA18A is 600-1000lbs per min and 1300lbs min for the E/F. I don't think this is really relevant though. A clean Hornet suffering a single engine failure will easily be able to climb away on one engine ... no real need to dump fuel to reduce weight.

 

Hornet has a max landing weight. (Like many fighters.) Though they wouldn't be in any hurry to dump and land... they'd climb and troubleshoot unless it was an absolutely dire emergency. (That's kind of the military way.)

Edited April 8, 2012 by aaron886

[Frostiken]

I'm sorry Frostiken but these enthusiasts are right about nozzles. Pictured here is RAAF F/A-18C and cold GE F404-400 engines look like this:

 

Nozzles are closed not open!

 

Okay? They're still wrong - the nozzles are screwed shut when under mil power as well, which they would've been under shortly after takeoff. To state that it was clearly a 'compressor stall' is utterly moronic, and then to go on to attribute that to the 2008 crash which has already been closed and most decided was not a compressor stall just ruins any shred of credibility you still have.

 

"The plane went straight up with no sound," John, an eyewitness, told WVEC. "And [then] he went right into a dive and I thought maybe it was a training exercise. And then, boom. I could hear it hit and I seen black smoke and instantly smelled jet fuel. ... I've never seen nothing like it before."

Eyewitnesses may lack a certain level of credibility but you will not mistake an engine in afterburner for a jet making 'no sound'. I guess they could've put it into AB right when they crashed? Edited April 9, 2012 by Frostiken

[Vekkinho]

You see, Croatia (the country I'm from) is looking for a modernization of it's airforce fighter fleet.

 

Among many options there's SAAB JAS-39C/D tender and I was in possesion of some Volvo Aero GE F404 RM12 flyers. It's a same engine as the one on F/A-18 but there's only one with Gripen.

 

So the thing they write in capital letters, and quite often is greater resistance to bird strikes.

[Yurgon]

You say that, then provide 800 words worth of fabricated explanations? Your "conclusions" are disjointed at best.

 

Your choice of words does not seem to indicate an intimate desire for discussion, but in case other readers are equally challenged by the simple task of text comprehension, I'd like to clarify a thing or two anyways.

 

"It never seizes to amaze me how many opinions are given and wild theories stated on single eye witness reports and some such."

 

I was trying to make the point that we should treat all sources as unreliable. If we take any single, individual point of data that has been presented in this thread, it is probably wrong, and any conclusion drawn from it will in turn be wrong, too.

 

But it got even funnier than that. On Apr 6 it was posted into this thread that according to official sources, the crash happened shortly after takeoff. On Apr 7 an individual posted that the aircraft probably crashed on final approach.

 

This thread is filled with individual points of data that are an outright contradiction to sources that had already been available, and no attempt at all has been made to clarify why the posters came to those conclusions (like alternate sources, some pal at Virginia Beach FD or so).

 

And finally I didn't even intend to offend any of the posters. In the truest meaning possible, I find it simply amazing how people come to such conclusions, apparently void of any sources.

 

Concerning fabricated explanations and disjointed conclusions, I'd be more than happy to go about any single point I made in my previous post. If you were to go into detail as to where you disagree and, more importantly, why, this may actually turn out to be of value to the two of us and this thread.

[vanir]

Personally I wouldn't have a real clue, but just shootin the breeze here I figure the crash photo looks like an engine failure, our radio news said eyewitnesses reported a fire under the wing, and it appears as Yurgon I think pointed out that no attempt was made to steer the craft away from population, and the whole thing happened about a minute after take off.

Another eyewitness report says plane went upwards then dive/crashed in what sounds like a classic low airspeed stall or sabre dance, instructor on board so he had to have grabbed controls by this point,

 

I'm going with engine failure at take off and low speed, there appears to be a fuel tank right in front of the engines on either side so one of those punctured and this was the fuel dump, I mean if we're talking about FOD for all this then I don't think it was a bird but something big and metal like a radio control plane or something from the residential area.

Unless of course it was a legitimate fuel dump but why.

 

Has anything like that happened before, a residential area that close to a fighter base caused danger? From things like footballs and radio control toys and stuff like that.

You'd think it would, I mean me and my mates did all sorts of screwed up things as kids, I wrecked a big earth mover tractor when I was 10. Had to climb a monster fence to get to it, but we were playing star wars and I decided it was the millenium falcon, captured by imperials...

[Vekkinho]

.

 

But it got even funnier than that. On Apr 6 it was posted into this thread that according to official sources, the crash happened shortly after takeoff. On Apr 7 an individual posted that the aircraft probably crashed on final approach.

 

 

 

Yeah, I guess we're just playing a broken telephone, 'cause some of the witnesses state the aircraft was circling the skies before it crashed.

 

No one mentioned how many aircraft were active in that part of the sky and was the MA really the only one around. If it circled while dumping fuel it couldn't be on a takeoff line from runway, rather on final.

 

Some state smoke from it's engines, was it smoke or dumped fuel vapors?

[Vekkinho]

 

Hornet has a max landing weight. (Like many fighters.) Though they wouldn't be in any hurry to dump and land... they'd climb and troubleshoot unless it was an absolutely dire emergency. (That's kind of the military way.)

 

Yes it does, however max landing weight is generally greater than max TO weight. Hornet is a sturdy bird, designed for carrier landing and can land heavy, fast and steep. 10.000lbs of onboard fuel is a joke, it's combat payload is greater than that and Hornets often return with full payload back to mothership.

 

Dumping the fuel was probably done in order to prevent major expolosion upon impact.

 

More fuel = more blast = greater fire= more damage.

 

I guess pilots knew the crash was inevitable, however by the intensity of thich black smoke I can say they haven't managed to dump any significant qty of fuel, there was lot of it left during crash.

Edited April 11, 2012 by Vekkinho

[aaron886]

But it got even funnier than that. On Apr 6 it was posted into this thread that according to official sources, the crash happened shortly after takeoff. On Apr 7 an individual posted that the aircraft probably crashed on final approach.

 

This thread is filled with individual points of data that are an outright contradiction

 

Or you just need a little help thinking critically. Sometimes takeoffs and landings happen quite close together... and in a Navy aircraft at an FRTP (Fleet Readiness Training Program... formerly RAG) airbase, it's not strange to see multiple trips around the pattern.

 

Stuff like that. I'm not going to get into a discourse with you because I don't think you have enough facts nor an appropriate level of knowledge concerning the aircraft or typical operations to warrant an argument. No offense. I don't have the facts either, that's why I haven't thrown out a bunch of assumptions.

 

 

Yes it does, however max landing weight is generally greater than max TO weight.

 

You've got it backwards. Think about it... airplanes don't get heavier in flight so there's no conceivable way that a weight restriction would increase during flight. (I'm not making this up, I'm providing a fact, seriously.) If I remember correctly, the Legacy Hornet has a field MTOW of 51,900 lbs GW. For field landings, 39,000 lbs GW. (A flared landing... an arrested/FCLP landing is ~33,000 lbs)

 

Hornet is a sturdy bird, designed for carrier landing and can land heavy, fast and steep. 10.000lbs of onboard fuel is a joke, it's combat payload is greater than that and Hornets often return with full payload back to mothership.

 

Yeah it's pretty sturdy but it's not magical. The Superhornet does have greater bringback capability but neither one would ever/could ever land with a "full payload" on the "mothership." :smilewink: To be fair, it would matter what the aircraft was carrying. A Legacy hornet without drop tanks is a pretty rare sight. Either way, with one engine, operating procedures may call for weight reduction prior to landing as a safety measure.

 

Dumping the fuel was probably done in order to prevent major expolosion upon impact.

 

That's a pretty silly conclusion if you think about how long it would take to dump an appreciable amount of fuel.

 

Regardless, none of this matters because we don't know whether the aircraft was dumping fuel or not. More importantly, I'll say it again, a Navy aircraft would not have remained in the pattern and forced a quick landing with an engine failure. An engine failure is a big deal, but it's not a life or death emergency... they would have climbed away from the field on the good engine (with ease and very little change in directional control) and troubleshooted the problem... that's the standard course of action for military aviators.

 

The way everything took place close to the ground leads me to believe there was something a little more sinister involved. We'll see! No point attempting to draw conclusions, let's just be thankful that nobody was hurt.

[Vekkinho]

 

 

 

You've got it backwards. Think about it... airplanes don't get heavier in flight so there's no conceivable way that a weight restriction would increase during flight. (I'm not making this up, I'm providing a fact, seriously.) If I remember correctly, the Legacy Hornet has a field MTOW of 51,900 lbs GW. For field landings, 39,000 lbs GW. (A flared landing... an arrested/FCLP landing is ~33,000 lbs)

 

 

No, you got it wrong! If an aircraft weighting 25 tons can takeoff it can land as well...Airframe structure and landing gear is designed to withstand Max TO weight landings...

[aaron886]

No, you got it wrong! If an aircraft weighting 25 tons can takeoff it can land as well...Airframe structure and landing gear is designed to withstand Max TO weight landings...

 

:doh: If you won't listen to me, I won't bother.

[EtherealN]

No, you got it wrong! If an aircraft weighting 25 tons can takeoff it can land as well...Airframe structure and landing gear is designed to withstand Max TO weight landings...

 

No. You do NOT need a plane to be able to perform landings at the same weight as MTOW. There is a reason why aircraft have an MTOW and an MLW. Think about it - when you you ever need to land at MTOW? The simple fact of ever lifting off means you'll land below MTOW - an aircraft that's flying is burning fuel and is therefore reducing it's weight.

 

This is one reason to have fuel dumping systems. The F-111 didn't get it's "dump-and-burn" kit to make pretty flypasts at airshows. If got the dumper such that it can quickly land if there is an emergency shortly after takeoff (and lighting AB happens to turn it on fire, which is practical for avoiding the spraying of built-up areas with aviation fuel).

 

According to USOCOST.net (who apparently got their numbers from the navy), for an F/A-18 E/F, MTOW is 66klbs, MLW is 50.6klbs. (42.9klbs for carrier operations)

 

Nothing strange at all in this - besides the whole expected weight thing, the aircraft suffers bigger stresses on landings than it does on takeoff.

 

You can pick up a manual for an airliner as well and see the differences for those aircraft (having less issues with classifications etcetera that way), and you'll find the same thing: they are not designed to be capable of landing at MTOW. They need to burn weight first.

Edited April 13, 2012 by EtherealN

[Vekkinho]

No. You do NOT need a plane to be able to perform landings at the same weight as MTOW. There is a reason why aircraft have an MTOW and an MLW. Think about it - when you you ever need to land at MTOW? The simple fact of ever lifting off means you'll land below MTOW - an aircraft that's flying is burning fuel and is therefore reducing it's weight.

 

 

You're both talking numbers and this is leading you astray.

 

Besides you said it above but didn't basically understand what you said.

 

Rather think about stress on a MLG and airframe. There are some Gs active when you touch the runway so MLW of 50.6klbs can easily turn to 100k lbs with 2G stress. Yet thankfully not too many MLG failures or airframe writeoffs. So forces acting upon aircraft in MLW usually max MTOW as you can see from the equasion.

Edited April 13, 2012 by Vekkinho

[aaron886]

You're both talking numbers and this is leading you astray.

 

Besides you said it above but didn't basically understand what you said.

 

Rather think about stress on a MLG and airframe. There are some Gs active when you touch the runway so MLW of 50.6klbs can easily turn to 100k lbs with 2G stress. Yet thankfully not too many MLG failures or airframe writeoffs. So forces acting upon aircraft in MLW usually max MTOW as you can see from the equasion.

 

Do you usually stuff your head in the sand when presented with overwhelming evidence? :blink:

 

I understood perfectly everything I said. I'm not making up an answer, I'm literally stating fact. (You do know what facts are, right?) A maximum landing weight is ALWAYS less than a maximum takeoff weight. Let me state some obvious reasons:

 

 

• Aircraft cannot get heavier. (A restriction will not exist if it can never occur. This is like an airplane having a maximum underwater diving depth or something.)
  

 

• Landings involve impact forces. Takeoffs do not. You JUST said so above. (jackiechan.jpg?!)
  

 

A landing weight restriction exists to keep the aircraft within stress limits. (Among other things) A heavier aircraft will be subject to a greater force. Force = Mass * Acceleration... Given a constant acceleration, the mass (weight) of the aircraft will determine the amount of stress applied to the airframe.

 

A takeoff weight restriction exists to keep the aircraft from running off the runway. Or over-stressing the wings in some cases. (ZFW/Zero fuel weight.) An aircraft can only produce so much lift, and to do so requires accelerating to a safe rotation/climb speed. If the aircraft is too heavy, it might run down a 15,000 foot runway and still not get airborne.

 

 

Please tell me this is enough to set you straight...

Edited April 13, 2012 by aaron886

[Vekkinho]

 

• Aircraft cannot get heavier. (A restriction will not exist if it can never occur. This is like an airplane having a maximum underwater diving depth or something.)
  

 

 

It can. Aircraft, especially carrier birds often launch with Max weapn payload but with fuel qty reduced in order to stay within MTOW. More weapons = less fuel. They fill both internal and external tanks later on by hooking to a tanker...

 

Read A-10 over Kosovo, aircraft fully loaded with weapons but not fully loaded with fuel would head for tanker straight after takeoff to fill up their tanks.

[EtherealN]

Rather think about stress on a MLG and airframe. There are some Gs active when you touch the runway so MLW of 50.6klbs can easily turn to 100k lbs with 2G stress. Yet thankfully not too many MLG failures or airframe writeoffs. So forces acting upon aircraft in MLW usually max MTOW as you can see from the equasion.

 

That's the point though - the restriction is there specifically because landing involves impact forces. An absolutely perfect landing can probably be done above MLW. But your margins for error are dramatically decreased.

 

And you can't say aircraft land at above MTOW just because you count G-forces in one case and not in the other, since the MLW is specifically calculated to include those expected G-forces - that is, if you expect 2G forces on landing, and the limit of your gears when under 2G's are 50klbs, then your MLW is 50klbs.

 

Like Aaron said, these are restrictions applied onto operation of the aircraft. You can go on exercises regarding the actual impact forces here and there, fact is that for a given aircraft you have specific MTOW's and MLW's, and the MLW is usually lower than your MTOW. Saying that the forces acting upon the aircraft on landing are greater than in takeoff does not make MLW higher - rather, it tells you specifically why MLW is lower than MTOW.

 

If your approach were to be accepted, you'd have a whole string of MLW's. "What's my MLW at 1G? At 2G? At 3G?" etcetera. That's not the way it's done. You have your MLW, and that's that. You then either perform a landing, or burn weight until below that MLW. The only case where you'll land above MLW is if you really really don't have a choice, which usually means you are in an extremely severe emergency.

 

What I think is confusing you is that you are taking a weight, adding G-forces, and then counting this as "being above MTOW". That is, however, not what anyone else means when they talk about aircraft weight for landing purposes. So we are talking across each other.

[Eddie]

Max landing weight is never greater than max take-off weight. Period.

 

You can get confused about G or any other random number you like, but the fact doesn't change. If the flight manual says the max landing weight is 50,600lbs (as is the case for a field landing in the Super Hornet), then the max landing weight is 50,600lbs, end of discussion.

 

Yes, aircraft can gain weight during flight, you are totally correct there. We often launch aircraft at reduced internal fuel on operations and they then head direct to the tanker to fill the tanks (mainly in cases where a heavy payload is required, or the airfield is in hot & high conditions). But that still doesn't change the max landing weight.

[tflash]

As I understood it, fuel load is also calculated on what you can have as loading for landing. Aircraft that need to do a landing with full tanks often do a few circles to reduce weight or dump fuel, don't they?

 

Super Hornet is also touted as having a higher bring-back capability than Hornet, something which implies that a Hornet normally does not recover to the aicrfat carrier with the same load as while taking off.

 

In the Bosnia Campaign many fighters dumped coslty unexpended ammo for the Italian Coast to match their bring-back capability.

[Eddie]

Carrier landing weight limits are 44,000lbs for the Super Hornet and 33,000lbs for the Legacy Hornet. Field landng weights are 50,600 for the Super Hornet and 39,000lbs for the Legacy Hornet.

 

Carrier catapult launch weights are 66,000lbs for the Super Hornet and 51,900lbs for the Legacy Hornet.

 

So as you can see, while an aircraft may be able to takeoff with full fuel and a good weapons load, if landing is necessary soon after takeoff it is likely to require dumping fuel and/or jettisoning ordnance.

[tflash]

Some discussion into possible causes of the crash, including an interesting mishap table at the end of the article: http://hamptonroads.com/2012/04/navy-explore-catastrophic-breakdown-scenarios

[Vekkinho]

^^^^

We speculate but so do others...