The relatives of children killed in the Germanwings plane crash have demanded an apology from the airline’s parent firm, Lufthansa, saying it ignored them and offered an “insulting” payout.
The letter from parents in Haltern, Germany, said Lufthansa CEO Carsten Spohr prioritised customers over them.
The airline said Mr Spohr had spoken with families. It has pledged to pay them up to €85,000 (£60,000; $93,000).
A Germanwings co-pilot is suspected of deliberately crashing the plane.
All 150 people aboard the Airbus 320, flying from Barcelona to Duesseldorf, were killed when the plane came down in March.
Investigators say co-pilot Andreas Lubitz locked the captain out of the cockpit before beginning a descent into the French Alps.
Lubitz is known to have suffered depression in the past. Lufthansa twice refused to renew his medical certificate in 2009 because of the condition, according to a preliminary report by French accident investigators.
The parents of 16 children, who were part of a school trip from Haltern that was travelling aboard the plane, said Mr Spohr had failed to apologise for the crash.
They said the airline should have said sorry for permitting Lubitz to fly despite his medical history. They also said Lufthansa had not yet apologised for failing to apply a rule – enforced by some carriers – that would have required two people to stay in the cockpit at all times.
The letter (in German) criticised Mr Spohr for not having spoken with the bereaved and for ignoring invitations to attend the funerals.
“We have not heard from you,” it said. “A couple of personal words in conversation with you would have shown us that you weren’t just there for the public but for us too.”
The letter also said the parents were deeply offended by a compensation offer, saying the sum “deeply insults us, and above all else our children”.
A Lufthansa spokesman, quoted by the Associated Press news agency, said Mr Spohr had tried his best to talk to the families and had attended several memorial services.
“Mr Spohr was in touch with many relatives and friends and family of the victims but it’s obvious that he was not able to be in personal touch with each and every one of the more than 1,000 relatives that we have,” the spokesman said.
Mr Spohr had spoken to some parents of the Haltern schoolchildren, he added.
The airline is currently negotiating a payout to the relatives of those killed in the crash. Reports say the airline has offered €25,000 to the families, with an additional €10,000 for immediate kin of the dead.
The €25,000 offer will be given on top of €50,000 already paid as immediate financial assistance, according to Reuters.
Lufthansa said in April that it had set aside $300m to cover costs arising from the crash, including compensation for the families.