I was reading this article about the last combat flight of an F-14 Tomcat and was shocked to discover these maintenance figures:
The decision to incorporate the Super Hornet and decommission the F-14 is mainly due to high amount of maintenance required to keep the Tomcats operational. On average, an F-14 requires nearly 50 maintenance hours for every flight hour, while the Super Hornet requires five to 10 maintenance hours for every flight hour.
Holy crap! 50 to 1?! That ratio is completely insane!
I can't imagine what general aviation would be like if we had to deal with such obscene costs. Actually, I can. General aviation simply wouldn't exist.
A typical rate for an aircraft mechanic in a decent maintenance facility is $60/hour. If you flew your 4 seat $75,000 Maule or Cessna 50 hours per year, that'd be $150,000 in maintenance costs every year. At that point, you might as well just buy a new plane each time it was due for an inspection.
Posted by jzawodn at February 22, 2006 09:39 PM
Sorry, we in Germany call that a "Milchmädchenrechnung" - you mix numbers that don't fit together.
Sounds like the 'timesheet' effect:
You are hired for 40 hours /week, you have to attribute all your hours to some project, even when there's nothing to do.
I use to book mine against 'maintenance' or 'support', that sounds like the aircraft maintenance engineers do the same thing.
I vaguely recall reading some other military aircraft stats that surprised me. Some writer claimed that in WWII a Spitfire could get off the ground in 12 minutes. That time is between the scramble alarm and wheels-up, and includes the time for the pilot to run to the plane and get it fired up. But a modern jet interceptor (I think they used the F-14 as the example) takes over an hour to get off the ground. The vast majority of that time is spent warming up the avionics and running the checklist.
I bet alot of the maintenance time is waiting for dwindling spare parts to be shipped and inspections for wear to the airframes.
In the last few years the F-14 transitioned from a pure interceptor/fighter to a fighter/bomber. That resulted in more payload being carried and probably more airframe stress. The Air Force had a bunch of wings fall off after the F-16 (originally designed to carry 6-8 air to air missles) started carrying heavy bombs and AGMs.
If your car had the maintenance costs of a F1-racer you couldn't afford to drive either.
But man... if your Cessna could do what a F-14 can do, you'd be paying... and gladly :-).
The F-14's variable sweep wings would have contributed a lot of maintenance?
And as for throwing away the plane, isn't that exactly what the russians used to do with their jet engines once some of the models reached x number of hours? Was cheaper to build a new one.
It should also be noted that there are only ~210 F-14s in service. 157 are F-14A/B and 53 are D variants. The first flight was in 1970. They were originally designed for 6,000 flight hours. Currently they are certified for 7,350 flight hours with a potential extension for 8-9,000.
The first D was delivered in Feb of 1990.
F-14Bs are supposed to begin retirement in 2007 and the Ds in 2008. All of them should be phased out 2010.
This has nothing to do with your post, other than explaining that the F-14 is an old bird and will be going the way of the dodo soon. ;)
Yea, but your Cessna doesn't go Supersonic, pull 9G's, do land (pound) on a carrier, etc.
BTW, I bet a good chunk of that maintenance cost/time is electronics - lotta old radar/avionics gear in the F-14's. Ditto previous posters comments about swept wings which adds a lotta complexity.
While it is true that they require lots of time on the ground, don't forget to keep in mind that the professional military maintenance personnel take that into account and strive to maintain aircraft sortie rates and availability numbers as high as possible. It isn't uncommon for an Air Force wing commander to have more than 90% of his or her aircraft available at all times. That's not bad given the numbers you've got on maintenance time. It’s epically remarkable given today’s high tempo environment.
Charles:
Any aircraft can be placed on alert and many crews practice just that to this very day. When on alert everything in the jet is ready to go, the engines are run and then turned off making the aircraft ready to launch within five minutes. Now compare that to what they were doing in WWII and you'll see that with the added maintenance required today it’s an even bigger feat.
But you're right Jeremy...my dream of owning my own T-38 someday is going to cost me. :-)
You know, it occurred to me, this discussion is missing a valuable data point: the maintenance required on privately owned military jets. Does anyone know Larry Ellison or someone on his MIG-21 ground crew?
Well General Aviation would never have to deal with costs like that because it involves capitalism! Someone would release a new plane that wouldn't require as much maintaince as the status quo, then someone would release a competitor, etc. Things don't work that way in the government.
The high maintenance is one of the things they are trying to lower with the new jets. The F22 which came out last year should be a lot better and the Joint Strike Fighter is supposed to be even better than that in the end.
I used to be a nav in the F-111. In a lot of ways the F-14 is the son of the F-111, they had the same motors, same general configuration, and many of the same engineers worked on both. Gruman made a Navy version of the F-111 (F-111B) before they did the F-14.
The F-14 was kind of like an F-111 that had gone to the gym and lost a lot of weight.
The F-111 was said to require about 80 hours of maintenance per hour of flight. I don't think that was too far off.
Of course if the wings on our Cessnas moved in flight, if we had 3 radars, if we flew at 200 feet and 500 knots, if we carried radar detectors and radar jammers, and if we had a fully enclosed escape pod we could use whenever we had a Cirrus moment, then it would take a lot more time to maintain our Cessna also.
I used to work on the F-14 avionics when I was in the Navy. I am not sure as to how accurate the numbers are compared to a Hornet, but let's say for argument sake they are accurate.
The Tomcat is a an old bird, but the avionics were exceptionally hard to work on. There were some gripes that took some time, but overall, not that bad. You pull a box, and you pushed a new one into place. The transmitter and antenna for the AWG9 was a PITA, but just heavy, but didn't take that long to fix.
Wiring problems on the otherhand were a nightmare, because you were normally chasing them through bulkheads, etc. Those are what took the longest if memory serves.
I really think though that the correlation of maintenance hours has to do with the scheduled maintenance more than the unscheduled. Every 100 hours a bird would come in for a phase inspection and be down for a while. You also had the 7/28/365 day inspections that were a problem.
As far as gouging the numbers, I'm sure some of that goes on, as that is how the manning levels were determined. Then again, we had really no need to fill out a time sheet as Navy maintenance is a little different than that in the civilian world, at least I never got paid by the hour;)
The airframe, electrical, power plant and line work took some time as well, but not as much as you would think;) Afterall, they are landing on a carrier and are heavy planes.
Just some thoughts though.
That's a typical shop rate. I don't know how much of that goes into the mechanic's pocket.
Hey Jermey,
Its not about the craft, its about the payload ..!!
heres the(some) facts
I was in a hanger the other day and saw a Stemme being annualed. I was impressed that the annual took over 40 hours (about $2500 of mechanic time). I guess everything is relative.
I can imagine. The Stemme is a beautiful, yet complex and big plane.
Jeremy... I have 600 hours in F-14's (Radar Intercept Officer RIO in VF-302 ie Fighter Squadron 302 the "Stallions" now decommissioned). We were based at "Fightertown" Naval Air Station Miramar (San Diego). I flew them for 4 years, while I was --honest, I'm not making this up-- age 38 to 42 (before that I flew F-4's; first Navy flight was 1970).
F-14 maintenance was a nightmare. On any given day, a 12-airplane squadron might start the day with 4 servicable aircraft, generally ending the day with 2 serviceable aircraft. More often than not, we would have 2 flightworthy aircraft all through the day (thought not the same 2 aircraft).
Note that in the Navy, each individual squadron has its' own maintenance people, so the squadrons can deply as a "single basic unit" unlike the USAF where you deploy a fighter squadron, a separate maintenance squadron etc. This is inefficient from a fix/fly perspective. And the aircrew is in daily contact with the fixers (yikes do they work hard, every day, all day) and you learn the fixers names as you would your work-buddies (although yes "rank" and "sir" plays into the equation).
Mass-movement ("going somewhere") with 6+ airplanes was a workaholic nightmare (squadron = 10 airplanes). For seagoing operations (we had to carrier-qualify once/year = 5 carrier day-landings) we had head-of-the-line status for spare parts (this helped a lot).
The maintenance/flight-hour ratio is *not* derived from dividing the flight-hours by the manning level of the maint.dept. The Navy keeps reasonable accounting of actual-time-spent (although not a good accounting of the efficiency of the time spent).
Points that skew the ratio: Taking a part back to the shop and "working on it" as opposed to the stuff that gets sent back to offsite repair (in this case the "waiting around" factor is real). Also F-14 "routine maintenance" ie what you would call "100hr inspections" etc was horrid. Simple R&R of a part (ie "diagnostic time" was nil) could be an all-day-affair. *Radar sucked up hundreds of hours/week*.
Note that at-sea, corrosion-control is the biggest job (by far). So any airplane with modern/improved corrosion-resistance will have a greatly reduced maintenance/flight ratio. F-18 is a fair bit of composite so "better". I have one flight in F-18, memorable.
In closing, the usage of your airplanes matters a lot. If you do ACM ("dogfighting") a lot (ie my squadron) the ratio is skewed because the flights are short (and the jets beat-up). In the fleet, emphasis is on long-flights (2-4 hours) so the maintenance/fly time "looks better".
Regarding your analysis of the $65/hr mechanic and the 50:1 ratio and "cheaper to buy a new airplane" well OK but would your new airplane go Mach-2? Land on aircraft carriers? Fly 500 miles, bomb somebody, and come home (Note current fleet use uses F-14 as bombers as well as fighters). See? "Capability requires complexity".
In closing, wing-sweep is not a significant maintenance item (although the "inflatable bag" that seals the trailing-edge/fuselage gap during wing-sweep is a pain to replace at the stated interval).
Sea story: I flew more-than-everybody because when we transitioned to F-14's I was allowed to transition only because I volunteered as "check-flight-RIO" ie flew the PMCF post-maintenance check-flights (but note this is not a credential; any pilot/RIO can fly PMCF). Nobody wanted to do this, so I was the last-RIO-selected. Trust me this makes me a World Expert in flying "really scary jets". Reservists are allocated 120 hours/year (pilots-only; it is assumed RIO's will be similarly crewed). Ha! In my last 2 years in the squadron I flew 200+ hours, so some RIO's were dogging it.
Paul P.
Oops... Forgot to mention that the last two F-14 squadrons in the fleet are back from Mediterranean/Iraq cruise and are all heading to the boneyard this year. Fleet-introduction was 1973. Roughly the same time-in-service as the F-4 Phantom.
At this years' Tailhook Reunion (Reno) I mentioned that Naval Flight Officers (NFO's like me F-14 radar operators etc, all "aircrew rated" but non-pilot) seemed to be overlooked/shortchanged.
By buddy told me "P-Ski, we have gone the way of the tailgunner. We're now just a footnote in history".
A sad way to end a career I think... "footnote in history"
P.
Ref: "But a modern jet interceptor (I think they used the F-14 as the example) takes over an hour to get off the ground."
Launch-time depends on the mission. F-14 crank-to-launch is about a half-hour (includes taxi etc).
But F-14's aboard ship sometimes stand what is called "5-minute alert" where it is on a "cold" catapult (ie not "in tension") and all-shut-down) ie no "hot avionics" etc). From this point it must be capable of being airborne in 5 minutes, and this is achieved regularly.
For a normal carrier cycle, you'll be in the jet about a half-hour before launch (shorter if you're spotted on a catapult).
Incidently, catapult-speed has nothing to do with size/weight of the jet. Only "end speed" matters, and is a function of aircraft stall-speed at the launch-weight. The fleet worst-case was a full-gross-load F-4 (58,000-lbs loaded with max-bombs ie how we flew them in Vietnam). The end-speed was 160 knots. A catapult is approx 270 feet long. 160 knots is approx 185mph so 0-185mph in 270' in 2.5 seconds.
Everything you ever wanted to know about aircraft carrier operations: http://www.fas.org/man/dod-101/sys/ship/cv.htm
Apologies for being a Blog-hog...
Paul P.
No worries. It's interesting stuff--at least to me. :-)
Jeremy: Please allow me to send an aviation-note:
Jim Howard: Your site did not have a click "send email" that I could see (but I'm a computer-zero I swear). I'm at pencipa@yahoo.com
But you said "I used to be a nav in the F-111. In a lot of ways the F-14 is the son of the F-111, they had the same motors, same general configuration, and many of the same engineers worked on both."
True, and here's another F-111 clip I bet you did *not* know...
The B-2 bomber was designed as a replacement for F-111, *not* B-1 or B-52. *F-111*. As-designed it has 1 pilot, 1 navigator just like F-111. *All* of the USAF aircrew within the B-2 plant (through Critical Design Review CDR) were F-111 aircrew (pilot/nav pairs). The USAF crewstation guys (pilot/nav) were Testerman/Winkler.
In the mid-1980's I was on the B-2 crewstation development team (Northrop) and spent a week living with F-111 crews at Plattsburg AFB. To a Navy guy (I had completed active duty but was flying F-4's in the Reserves as a radar operator), *this was hell-on-earth* with daily school-drills, "standing alert" and crushing nuke-security burden (the Navy simply ignores this stuff). Oh yeah I saw STANEVAL ("standardization/evaluation") mercilessly grill the aircrew both in tests and the simulator *every single day* (no STANEVAL equivalent in the Navy).
I came away from Plattsburgh with a HUGE appreciation for USAF aircrew. Wow did they know their stuff. And then go out and fly 400-kts terrain-following *at night* yikes.
Politics: Before B-2 1st-flight, the USAF pilots rioted. Somehow pilot/nav was no longer Ok, all of a sudden "2-pilots" were mandatory (this is complete BS, B-2 cockpit is designed from day-1 as a single-pilot cockpit).
I could go on, but this is Jeremy's blog...
Paul P.
Northrop (24 years, retired)
Naval aviator (20 years, retired. 16 Navy flying years w/o a desk job which to put it bluntly is "not very bright")
PS>> Jeremy... Wow you struck a lot of chords with this topic!
This may be a unrealistic question, but being a huge fan of the Tomcat, I was wondering wether you were able to purchase old parts of a Tomcat or wether you new about the right paths to go down to do this. What I was hoping to get my hands on was one of the tail fins of a plane. Please let me know your thoughts.
Kind Regards
Dan
Well, I was in the Army in the Vietnam era and the CH-47 had a pretty high number of maintenance hours per flight hour. It was classified and probably still is as updated versions of this helicopter are still in the active inventory. However, that isn't my question. I was wondering what the maintenance ratio was for the various WWII fighters used for training, but not in combat, since battle damage is not what we normally mean when using the term, 'maintenance'.
