Crash in Las Cruces, NM kills 4

Why can't a recip operate on Jet-A? We all know that it can't, I just don't understand why it can't.

Both witnesses reported seeing smoke trailing the right engine, so Jet-A obviously kills an engine very quickly.
 
Why can't a recip operate on Jet-A? We all know that it can't, I just don't understand why it can't.

Both witnesses reported seeing smoke trailing the right engine, so Jet-A obviously kills an engine very quickly.
Jet A has a very low resistance to detonation/preignition. That's why diesels run it. In something like a GTSIO520 the fuel/air mixture in the cylinder is going to be hot enough that with Jet A in there it will self-ignite far before the spark plugs fire, which means that the fuel air mixture will be burning while the piston is still coming up on the compression stroke. This sends pressures and temperatures in the cylinder through the roof and results in things like reduction in power, cylinder heads popping off, and holes being burned in pistons. I guess it's important to note that diesels are still recips and they run great on Jet A, the key is that spark ignition engines can't run it.
 
Why can't a recip operate on Jet-A? We all know that it can't, I just don't understand why it can't.

A recip CAN run on Jet-A (and or diesel). A diesel engine is a reciprocating piston engine. Diesel/Jet-A/home heating oil is all Kerosene in varring degrees of purity.

A engine designed to run on gasoline ignited by spark plugs will suffer massive detonation/preignition problems.
 
Sad to hear that happened. I fly around in an AvGas powered DA-42. Whenever, I'm out on cross countries, I always check the FBO receipt to make sure the plane was fueled up with AvGas and not Jet-A since a lot of Twin Stars out there are diesels. I'm always extra careful with that, and I have even had line guys initially think it did take Jet-A. It only takes one line guy assuming a fuel type to mess up a person's day. It's really cool to hear about what an impact he had on those around him. May he RIP, and be remembered for that impact he had on those around him.
 
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Jet A has a very low resistance to detonation/preignition. That's why diesels run it. In something like a GTSIO520 the fuel/air mixture in the cylinder is going to be hot enough that with Jet A in there it will self-ignite far before the spark plugs fire, which means that the fuel air mixture will be burning while the piston is still coming up on the compression stroke. This sends pressures and temperatures in the cylinder through the roof and results in things like reduction in power, cylinder heads popping off, and holes being burned in pistons. I guess it's important to note that diesels are still recips and they run great on Jet A, the key is that spark ignition engines can't run it.
@tomokc you might enjoy this - among Deakin's other columns, this is an analysis of an inflight engine failure captured by a sophisticated engine monitor. ALL of his engine-related columns are really quite good too and provide far better explanations of what's really going on in there than anything you'll see out of the FAA or even engine manufacturers.
 
Beyond the sadness surrounding this accident, is this Preliminary Report that states the pilot was actively involved in the fueling process. Earlier comments in this thread about how a pilot should be involved in the fueling has been set aside.
This pilot, may he and the others RIP, WAS present and engaged in the fueling but must have been pre-occupied with other tasks or not thinking of the task at hand.

Bad deal for all, I empathize with the fueler as well, tough thing to live with.....
 
Sad to hear that happened. I fly around in an AvGas powered DA-42. Whenever, I'm out on cross countries, I always check the FBO receipt to make sure the plane was fueled up with AvGas and not Jet-A since a lot of Twin Stars out there are diesels. I'm always extra careful with that, and I have even had line guys initially think it did take Jet-A. It only takes one line guy assuming a fuel type to mess up a person's day. It's really cool to hear about what an impact he had on those around him. May he RIP, and be remembered for that impact he had on those around him.
The last FBO I worked at a guy did the opposite, putting 100LL in a diesel DA-42. Thankfully they caught it, although I hear it's not as bad as the other way around.
 
Beyond the sadness surrounding this accident, is this Preliminary Report that states the pilot was actively involved in the fueling process. Earlier comments in this thread about how a pilot should be involved in the fueling has been set aside.
This pilot, may he and the others RIP, WAS present and engaged in the fueling but must have been pre-occupied with other tasks or not thinking of the task at hand.

Bad deal for all, I empathize with the fueler as well, tough thing to live with.....

Not exactly what the NTSB said, though it is possible he was involved in the fueling. What the NTSB preliminary report states is:

" The pilot was still seated in the cockpit when he gave the line service technician a verbal order for a total of forty gallons of fuel. The line service technician drove the fuel truck to the front of the airplane and refueled the airplane putting 20 gallons in each wing. The pilot then assisted the line service technician with replacing both fuel caps. They both walked into the office and the pilot signed the machine printed fuel ticket."

All it says is that the pilot was in his seat when the service guy came up to the airplane and asked for 20 gallons in each wing; and that the pilot assisted in replacing the fuel caps. Nothing about actually helping in the fueling process beyond this.

My guess is that the pilot knew the service technician. The pilot was from this area, was a ramp rat before becoming a pilot (at 5T6), and flew into KLRU on a regular basis.
Since this was a 135 air ambulance flight even if he was present the PIC probably would have had other duties- W&B, performance, flight plan, check of weather, check with company, loading of patient. Probably assumed the ramper knew what to do.
As for the ramper, the air ambulance company sometimes flew a King Air, sometimes the 414. Ramper assumed it was a King Air. I actually feel for the guy. Probably some young kid with little training who made a simple mistake but will have to live with this for the rest of his life.
 
Yeah, that's pretty much what it states. My bet is the final report will state what I did. Contributing to the accident - He was there, involved, and distracted during the fueling process.

To me, ordering the fuel, being the the very near vicinity while the fueling occurs, replacing a fuel cap, signing the fuel ticket (which I would be willing to bet reflects the amount and TYPE of fuel provided) IS the fueling process. Although you described some of the task that may have been in his mind, you have stated almost exactly what I did. And that is that he was pre-occupied with other tasks and wasn't paying attention. Tomato.....Tomawto......whatever......
 
Yeah, that's pretty much what it states. My bet is the final report will state what I did. Contributing to the accident - He was there, involved, and distracted during the fueling process.

To me, ordering the fuel, being the the very near vicinity while the fueling occurs, replacing a fuel cap, signing the fuel ticket (which I would be willing to bet reflects the amount and TYPE of fuel provided) IS the fueling process. Although you described some of the task that may have been in his mind, you have stated almost exactly what I did. And that is that he was pre-occupied with other tasks and wasn't paying attention. Tomato.....Tomawto......whatever......

We won't know for sure until the final report, but my sources tell me that the fuel slip had "AVGAS" written on it rather than Jet-A.
So again, based upon a single source (the fueler), in a preliminary report you are making conjectures that may be true but are not supported by the report. How well if at all was the truck marked? Was the PIC actually present during the fueling or did he walk up when it was completed? Who knows at this point.
 
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It was reported last night on the local news that the Navy will not be bringing their T-44 detachment into Las Cruces for winter training. They've been doing this since 2001. The reason cited in the report is that the Navy has concerns about their aircraft receiving the proper fuel following the air ambulance crash.
 
It was reported last night on the local news that the Navy will not be bringing their T-44 detachment into Las Cruces for winter training. They've been doing this since 2001. The reason cited in the report is that the Navy has concerns about their aircraft receiving the proper fuel following the air ambulance crash.

As if that poor guy will ever make the same mistake again.. If he's even got a job anymore.

Fueling should always be checked by both sides.
 
Tried an online search but found nothing for this.. Every place I did line service, the Jet A nozzles were an oval shape and much larger than avgas, they wouldn't even fit into avgas openings. Do they make a smaller nozzle for some application?
 
Tried an online search but found nothing for this.. Every place I did line service, the Jet A nozzles were an oval shape and much larger than avgas, they wouldn't even fit into avgas openings. Do they make a smaller nozzle for some application?

That program has been in use since the early 80s, the oval Jet-A nozzles in order to prevent misfuelings; good innovative designs. The smaller nozzles however still exist, primarily for rotary wing aircraft that don't have receptacles that can accept the oval nozzle. Why this is, I'm not certain.
 
That program has been in use since the early 80s, the oval Jet-A nozzles in order to prevent misfuelings; good innovative designs. The smaller nozzles however still exist, primarily for rotary wing aircraft that don't have receptacles that can accept the oval nozzle. Why this is, I'm not certain.

Gotcha. I've fueled multiple types of jetA helos but have never seen that nozzle, heard of it though.

Seems like something that should be put on only when necessary, and removed afterwards.
 
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