|EAA AirVenture 2012 has just wrapped up. If you were fortunate to have gone this year (sorry to say I was not), and I asked if you saw any antique airplanes, you might mention seeing a Waco, a DC3 or Ford Tri-Motor. But what about a Learjet 35A, Citation II or Hawker 700? Early serial numbers of these venerable business jets are well into their golden years as they all were in production during the late 1970s. These and many other business jets are well past age 30.
In our aircraft cost databases, we assume that all the business aircraft are maintained more or less the same way with new parts replacing old, worn out parts. As many operators of long-out-of-production aircraft are finding out, this is not the most cost effective way to keep these aircraft flying.
First off, availability of new parts for older aircraft is becoming harder to find. Some non-OEM vendors are no longer in business, or they have been acquired and merged into different entities. They do not keep production lines open year round or may only build spares as needed.
Overhauling of serviceable components is also getting harder to accomplish. Sure, you can overhaul a generator multiple times, but what about the holes for the mounting bolts? Over time, you can only use "oversize" bolts so often before the component case is no longer serviceable.
To say that avionics have evolved since the mode 1970s is an understatement! Many of these older aircraft use what we euphemistically call steam gages. And relative to today’s technology, that statement is not too far off. Repairing these older instruments is becoming more costly, as are replacements. Glass cockpit upgrades are available, but at what cost?
Perhaps the toughest choices come with the engines. The first and second-generation business jet engines are all into their second, third or fourth overhaul cycle. Guaranteed engine maintenance program rates reflect this with rates much higher than current generation engines. The cost to overhaul a pair of these engines can run to more than the cost of the aircraft itself. Even with fresh engines, a 35-year old business jet will not double in selling price.
Look at the very popular Citation II. According to the Aircraft Bluebook Price Digest (Summer 2012), the selling price of a 1978 Citation II is $650,000. The basic overhaul price is about $350,000 per engine. Add in some cycle-limited items like rotor disks and impellers and the price jumps to over $500,000 – each!
Overhaul a pair of run-out engines on your 35-year old business jet and you will be lucky to get 50% back if you sell it. There are just too many of theses aircraft available for sale and at very low prices.
I have talked with more than one operator of aircraft like these who will not, and cannot, pay for an engine overhaul. Instead they look for a similar model year aircraft with engines in good condition with maybe 1,500 hours remaining until overhaul. They buy the second airplane, swap engines and part the rest out. This recycling method is more cost effective for many of these older business jets.
I doubt values on these “vintage” jets will ever recover. So it looks like we will see a steady dwindling of whole aircraft as we see two aircraft make one flyable aircraft and so on. Keeping these older business jets flying is becoming more of an exercise of scrounging and cannibalizing versus one of replacing/overhauling.
Maintaining older aircraft in this manner requires time, and decreases the aircraft availability. You need to have two or three aircraft to keep one in flyable condition! It can be done, but it is better suited to a flier that can live with low utilization and decreased availability. So enjoy these aircraft now, because it won't be to many more years at Oshkosh before a Learjet 35 is parked next to the Staggerwing!