The Philippine Air Force (PhAF) received a total of 37 F-5A and F-5B fighter aircraft from 1965 to 1998, but by 2005 only 10 were operational, and within that same year these 10 were retired from active service, leaving the defense of Philippine airspace to only a couple of AS-211 Basic Jet Trainers. The PNoy Administration of course just bought a dozen FA-50 Fighting Eagle aircraft, the first brand-new true fighter aircraft bought by the Philippines in almost 40 years, but in the back of my mind I’ve always wondered whether it is still possible to revive and even modernize our F-5s. After all, the more capable aircraft we have around to defend our skies, the better.
So what would be the benefits of having these overhauled and modernized F-5s? Well, countries like Singapore (F-5S) and Brazil (F-5EM) use theirs mainly as Lead In Fighter Trainers (LIFTs) and Interceptors, and with weapons/equipment like Multi-Mode Radars (MMR), Helmet Mounted Sights (HMS), High Off Boresight missiles and Beyond Visual Range (BVR) missiles, they are actually better armed and equipped for air combat than our FA-50s. The advantages of the FA-50s are that they would likely require less maintenance and have better availability because they are brand-new; And that they have a Fly-By-Wire (FBW) system and a built-in simulation system.
The importance of FBW technology on the FA-50s cannot be underestimated, it makes it easier and also much SAFER to fly than non-FBW aircraft like the F-5s. I am planning to blog more about FBW technology at a future date to stress its importance, especially with our Air Force.
‘Overhauls and Upgrades’
For these PhAF F-5s to be brought back into service, they will have to first go thru an OVERHAUL, which basically means:
– Dismantling the planes;
– Inspecting all the parts using various methods for defects;
– Refurbishing or replacing parts that were found to be defective;
– Re-assembling the entire airplane.
– After they are re-assembled, then further upgrades or modifications can be introduced into the aircraft.
Right now there are no shortage of companies which can do these as ALL of the F-5s currently in service in various air forces around the world have gone thru this process at least once in their lifetime. Although the price tend to vary depending on the upgrades introduced to the aircraft, their costs are surprisingly low. Here are some examples:
* Northrop Grumman‘s upgrade of 44 US Navy and former Swiss Air Force F-5E to F-5N standards in 2009, costs USD 1 million per aircraft. Work included overhaul, rewiring, upgrade of some avionics (navigation and radar display systems), replacement of some equipment (oxygen equipment and anti-skid brakes).
* Embraer‘s upgrade of 46 Brazilian Air Force F-5E to F-5EM standards in 2000, costing USD 5 million per aircraft. Work included addition of new equipment (aerial refuelling probe, Oxygen system, Fuel management system, etc.), new avionics (Grifo Radar, Radar Warning Receivers, Multi Function Color Displays, Dash Helmet Mounted Sight, etc.).
* ST Aerospace‘s upgrade of 49 Royal Singaporean Air Force F-5E/F to F-5S/T standards in 2001, costing USD 4.8 million per aircraft. Work included overhaul, new avionics (new Radar, Heads Up Display, Dash Helmet Mounted Sight, Multi-Function Displays, etc.) and other equipment upgrades (Hands on Throttle and Stick, etc.), also.
Aside from the companies listed above (all of which are still very much in business), a quick look in the internet reveals a couple more companies also doing overhauls and upgrades for the F-5, some of them are:
* Israeli Aerospace Industries Lahav Division – Offers overhauls and avionics upgrades for F-5 aircraft, has done work for Spain, Turkey, Thailand and Chile. Website is at http://www.iai.co.il/17866-37523-en/Business_Areas_Military_Aircraft_Upgrades.aspx?
* Tiger Century Aircraft – Offers overhaul and upgrades to various F-5 configurations like the F-5MR4 “Agile Tiger” or the F5R “Red TIger”. They also offer upgrade kits for aerial refueling, agility enhancement, AIM-9L/M capability, etc. Website is at http://tigercenturyaircraft.com/about
‘Logistical Parts Support’
Northrop Grumman, the original manufacturer of the F-5, has partnered with Switzerland’s RUAG Aviation to provide logistical parts support for the sustainment of F-5 aircrafts all over the world. Also, since the F-5 is still in service with roughly a dozen air forces, a couple of other logistics companies have cropped up offering similar logistical parts support services like Derco Aerospace Inc.. Tiger Century Aircraft initially mentioned above as doing overhauls and upgrades also offers logistical parts support services for the F-5s.
The maximum price for the overhauls and upgrades listed above is only around USD 5 million, and adjusting for inflation today that would only be around USD 7 million per aircraft. Now despite the overhauls and modernizations, these aircraft are still 2nd hand aircraft of an older design, hence they will need more maintenance requirements than brand new aircraft. Looking at the US Armed Forces’ record of maintaining their F-5Ns, they averaged around USD 970k per year per aircraft to keep their planes flying.
The US F-5Ns though are flown a LOT more in terms of flight hours and in a more aggressive manner than I imagine we would, hence it is possible that with less stressful flight hours our actual maintenance costs would actually be a lot lower, probably around half that price. Nevertheless, assuming the worst figure of USD 970k per aircraft per year, we could allocate that amou nt into our budget for an estimated timeframe of, say, 15 years, then that means a total cost of USD 14.5 million per aircraft for maintenance only, which would be more than TWICE the price of the aircraft’s overhaul and modernization. However, the total price (upgrade, modernization and annual maintenance cost) of USD 21.5 million per aircraft would actually still be lower than the USD 38 million (with Integrated Logistics Support) we paid for each of the FA-50s.
’F-5A versus F-5E’
Note though that the PhAF is operating F-5A Freedom Fighter aircraft, and not the F-5E Tiger II aircraft that other countries are still using up to now, and there are significant differences between the two models. Despite these differences, though, my guess is that parts availability will still be okay as long as Northrop is committed to sustaining the parts requirements for F-5s.
Below are the F-5Es major differences to the F-5A: 
– Fuselage is slightly longer by about 0.2 m and also wider, and its shape below the wings is straight instead of a “Coke-bottle” shape;
– Wingspan is longer by 0.43 m, and has a bigger Leading Edge Root Extension (LERX);
– Cockpit Layout;
– Ejection Seat, the F-5A uses the MB Mk 10L;
– Nose Landing Gear;
– Fuselage Pylon is bigger;
– More powerful engines necessitating the use of bigger intakes and additional louvres.
The first problem could be one of AVAILABILITY as they are EXPECTED to have MORE FREQUENT and LONGER PERIODS of maintenance compared to a spankingly brand new aircraft like the FA-50.
The second issue is that, looking at the US F-5N’s maintenance cost per year, it tends to vary a lot from year to year, from a low of USD 529k to a high of USD 1.52 million and with a Standard Deviation of over USD 500k, meaning on an annual basis you can expect the budget to deviate by around that much. This indicates a relatively large degree of unpredictability in terms of the maintenance costs of these aircraft. If the maintenance costs are below the annual budget set for them, then there’s no problem, but if they are HIGHER than the annual budget, then that might be a problem for our mediocre funding and procurement system as large adjustments will have to be made.
‘Limited Future Availability’
Any revival of our F-5s at this point in time will likely be the LAST one for them because most air forces are set to retire their F-5s by 2020, and once that happens the incentive for most of the overhaul/modernization/logistics companies to stay in business just won’t be there anymore.
Beyond 2020, Brazil will be the only country assured of having a significant number of F-5s still flying, and they are set to retire theirs by 2030. Once that happens, we may finally see the final demise of these F-5s from active service from almost all of the air forces of the world. It may be possible that some small countries may still operate them on their air forces beyond 2030, but it will likely be in very few numbers only.
It is still possible to revive our F-5s as of now, there are still many companies offering overhaul and modernization services and parts support is still strong. On the Pro side:
– Reviving them will give us more aircraft to use to defend against external aggressors;
– If the upgrade will be similar to the F-5S/EM standards then they will have better equipment and arms than the FA-50s;
However, on the downside:
– These F-5s with their non-FBW systems will be a little bit less safe and a little bit more difficult to fly than the FA-50s;
– They are also expected to have less availability due to their more frequent and longer maintenance requirements;
– The high degree of unpredictability of their maintenance costs could also prove to be challenging to our slow funding and procurement capability.
From a personal point of view, I initially had high hopes that these F-5s could be revived and still prove useful to us, but looking at the data and the scenarios, it may be just a little bit too complicated to maintain them, at least for us. True, they are a CHEAPER way to add more capable aircraft to our inventory than buying brand new aircraft, but there are just too many baggage that go along with it.
My opinion is that perhaps it would be better if we just allocate the money to upgrade the equipment and arms of the FA-50s, or if the PhAF really needs more aircraft, then it should perhaps just buy brand new aircraft like more FA-50s, or perhaps other Light Combat Aircraft like an updated version of the Hawk 200. They would be more expensive, but they will be safer, probably have more availability, and cheaper and easier to maintain. We may finally have to say goodbye to our F-5s for good, they have served us very well in defending our skies for decades …
^ Aquino confirms all 12 FA-50 fighter jets in by 2017,
^ Putting the Fight Back into the F-5,
^ Brazil’s F-5BR Fighter Fleet Upgrade Program,
^ Northrop F-5E/F Tiger II in Service with Singapore,
^ Northrop Grumman Signs Teaming Agreement With RUAG Aviation for F-5 Worldwide Sustainment and Life Cycle Logistics,
^ Derco Aerospace Inc. – About,
^ Supporting the USA’s F-5 Aggressor Fighters, 2008 – 2014,
^ F-5A Freedom Fighter,
^ Northrop F-5 Freedom Fighter,