AW169 Gear Down Transit
 

Hi all,

Purely a question for interest sake.

The local HEMS type helicopter service has a couple of AW169 that transit past my house a few times per day between their base and the hospital. Distance is about 15-20nm each way depending on route.

The helicopters are relatively new having replaced a similar number of BK117. Initially they were flying around with the gear up, but lately they are transiting gear down. I understand helis often hover gear down irrespective of whether they are landing, but why would you transit gear down assuming there isn’t a fault? What is the fuel burn penalty like and are you speed restricted?

Like I say, just curious watching them fly past like this.

Cheers

Could be a number of factors -

No need - such a short transit 7-10 minutes - gear cycles counted with subsequent overhaul life? I think 169 actuation is electric. Vle is probably pretty high.

Low transit - stops gear warning squealing at you?

169 with gear down doesn’t really lose all that much speed for same cruise power setting.

Also if the pilots have recently transitioned from skids and have never flown retractable gear before, then leaving it down for a short, busy sector (particularly if they fly SP) is one way of ensuring that the gear is down before landing.

Some 169s have fixed gear, it's an option.

The Kent, Surrey and Sussex Ambulance AW169s regularly transit past me on the way back from delivering patients at Kings College Hospital to Redhill (17 miles, I'm about midway) as well as heading off on the odd task and I've noticed them a few times recently with the gear down - wondered why. They do appear to have retractable gear looking at some of the pics on line.

There were teething troubles - see EASA AD No.: 2017-0164

As an interim measure to address a potential unsafe condition in the landing gear actuators found in some in early machines, Leonardo designed a modification to inhibit the LG retraction for helicopters equipped with affected retraction actuators, and issued Bollettino Tecnico 169-005, providing instructions to install that modification on in-service helicopters. Leonardo also designed a modification to remove affected retraction actuators, allowing delivery of helicopters still on the production line. Subsequently, Leonardo developed improved LG retraction actuators that allow restoring the LG intended function, and issued Mandatory Bollettino Tecnico 169-018, providing instructions to install those actuators on in-service helicopters. Leonardo issued Alert Service Bulletin (ASB) 169-023, providing additional instructions to install improved control box and proximity switches, and to protect repetitively the plungers of the NLG and MLG up down lock actuators against corrosion.

Consequently, EASA issued AD 2017-0110 to require modification of helicopters by removing all affected LG retraction actuators from service, installing the improved LG retraction actuators, control box and proximity switches, and a one-time application of corrosion inhibitor on the plungers of the NLG and MLG up down lock actuators. Leonardo ASB 169-023 provides instructions for repetitive application of corrosion inhibitor. Since this is considered as standard practice maintenance, those actions were not required by that AD.

Question: Are there machines currently in service that are not able to retract their gear?

Those manufactured as fixed gear aircraft certainly fit the bill.

The professional way to ensure that is to use the check list!

Absolutely Shy:ok: I took a number of pilots who had only ever flown skids and converted them to one with retractable gear - if you train them properly it shouldn't be a problem, don't just say 'gear down', look at the lights and confirm the indications. Then use the 150' alert to double check on short finals.

You've got to be professional first !

Totally agree and, despite that, a modern aircraft like the AW169 is supposed to have a landing gear warning, right?

I’m sure those involved are.

Just seen G-KSSC returning to Redhill, the gear appeared to be retracted on this occasion.

There are two likely reasons that the gear is likely to be left down.
1. The journey is short, so not worth it.
2. The maximum airspeed for lowering/raising the gear is 80 its, so if you're whompiting along at max chat, it may be thought easier to leave the gear down. (Yes, I know you have to slow down to land so why not do it then).
There are of course other reasons but for the cases pointed out, these two are my best guess.

VLO is 130 knots if the gear is modded. 80 knots if not modded.

From memory the std gear on the 169 is fixed with retractable being an option.