Here's the deal, from the mouth of the ARFF-qualed firefighter: me.
To foam or not to foam?
Yes...that is the question.
Years ago, airport ARFF stations had vehicles called "runway foam tenders" whose speciality was large-area foaming, specifically runways. At one time, foaming a runway was common for aircraft that were landing with gear malfunctions. Of course, the whole runway wouldn't be foamed, just about a 3000' X 100' swath of the runway, since if landing gear up, that's about the very max you can expect to slide. The benefits of foaming a runway aren't truly known; planes have landed both ways (with and without foam) with the results being pretty much the same. The older "protein foam" that was made from animal by-products was relatively thick, and provided a good cushion against friction/sparks; and was relatively cheap. The specialized foam tenders would lay down the foam, and the crash trucks would await the arrival of the aircraft.
Today, much has changed in the fire service, primarily due to $$$. Runway foam tenders were tough to maintain since, every time foam is used for training or actual use, the vehicle had to have the all the discharge lines purged of the foam with water in order to prevent corrosion of the internal components. That takes time and money. So runway foam tenders began to be phased out. Foam itself has changed too. The older protein foam has been replaced by Class B AFFF (Aqueous Film Forming Foam) or FFFP (Film Forming FlouroProtein). Both of these agents are newer foams used for Class B (flammible liquids) fires just like the older protein foam, but are a little thinner, are biodegradeable, and hence, cost more. Though it takes a little while to clean the foam off the runway, it takes no longer than it takes for the crash-recovery folks to remove the plane from the runway, so time isn't a factor here. Tactically speaking, with few runway foam tenders in service (in the USA, at least) anymore, then in order to prep a runway with foam, the ARFF trucks would have to do it themselves (which they're not really optimized to do, but they can), and thus deplete their own onboard supply of firefighting agent. At a large airport like DFW or LAS, you can probably get away with this. At somewhere like SDL, which has only one medium size ARFF truck and one small-size dry chemical/halon truck, you're a little more restricted as a fireground commander.
Now what would firefighter Mike have done had he been the CO? I would foam a runway if a crew requests it, no problem. My job as the ARFF crew is to comply as much as possible with the aircrew's needs. I caveat that with saying that I'll comply, while keeping the tactical needs of the situation in check. If it's an inbound Cessna that's landing gear up, and I have an Air Force Base-worth of ARFF vehicles, no problem. But in this case, if the pilot requests the runway be foamed, I'd be more than happy to do it, I'd just have tower inform the pilot that he'll need to hold for about 20-25 minutes (best case) while I have the ARFF vehicle lay down the foam swath, then get refilled at a nearby hydrant, then relocate to the runway mid-point, with the chemical truck at the approach end, water tender truck available, ambulance on scene, and additional call for at least one structural engine truck for backup manpower.
If the pilot can accept that delay in order for me to be happy with my tactical needs, then I as the fireground commander would be happy to give him that piece of mind. If I can give the pilot one less an item to worry about, then so it will be.
Just hope he doesn't do what one pilot did after we foamed a runway once, and come in with too much speed, float over the foam blanket, and land beyond!
To foam or not to foam?
Yes...that is the question.
Years ago, airport ARFF stations had vehicles called "runway foam tenders" whose speciality was large-area foaming, specifically runways. At one time, foaming a runway was common for aircraft that were landing with gear malfunctions. Of course, the whole runway wouldn't be foamed, just about a 3000' X 100' swath of the runway, since if landing gear up, that's about the very max you can expect to slide. The benefits of foaming a runway aren't truly known; planes have landed both ways (with and without foam) with the results being pretty much the same. The older "protein foam" that was made from animal by-products was relatively thick, and provided a good cushion against friction/sparks; and was relatively cheap. The specialized foam tenders would lay down the foam, and the crash trucks would await the arrival of the aircraft.
Today, much has changed in the fire service, primarily due to $$$. Runway foam tenders were tough to maintain since, every time foam is used for training or actual use, the vehicle had to have the all the discharge lines purged of the foam with water in order to prevent corrosion of the internal components. That takes time and money. So runway foam tenders began to be phased out. Foam itself has changed too. The older protein foam has been replaced by Class B AFFF (Aqueous Film Forming Foam) or FFFP (Film Forming FlouroProtein). Both of these agents are newer foams used for Class B (flammible liquids) fires just like the older protein foam, but are a little thinner, are biodegradeable, and hence, cost more. Though it takes a little while to clean the foam off the runway, it takes no longer than it takes for the crash-recovery folks to remove the plane from the runway, so time isn't a factor here. Tactically speaking, with few runway foam tenders in service (in the USA, at least) anymore, then in order to prep a runway with foam, the ARFF trucks would have to do it themselves (which they're not really optimized to do, but they can), and thus deplete their own onboard supply of firefighting agent. At a large airport like DFW or LAS, you can probably get away with this. At somewhere like SDL, which has only one medium size ARFF truck and one small-size dry chemical/halon truck, you're a little more restricted as a fireground commander.
Now what would firefighter Mike have done had he been the CO? I would foam a runway if a crew requests it, no problem. My job as the ARFF crew is to comply as much as possible with the aircrew's needs. I caveat that with saying that I'll comply, while keeping the tactical needs of the situation in check. If it's an inbound Cessna that's landing gear up, and I have an Air Force Base-worth of ARFF vehicles, no problem. But in this case, if the pilot requests the runway be foamed, I'd be more than happy to do it, I'd just have tower inform the pilot that he'll need to hold for about 20-25 minutes (best case) while I have the ARFF vehicle lay down the foam swath, then get refilled at a nearby hydrant, then relocate to the runway mid-point, with the chemical truck at the approach end, water tender truck available, ambulance on scene, and additional call for at least one structural engine truck for backup manpower.
If the pilot can accept that delay in order for me to be happy with my tactical needs, then I as the fireground commander would be happy to give him that piece of mind. If I can give the pilot one less an item to worry about, then so it will be.
Just hope he doesn't do what one pilot did after we foamed a runway once, and come in with too much speed, float over the foam blanket, and land beyond!
